Mastering HSDPA/HSUPA
Signaling
www.awardsolutions.com
Communicating Communications
© 2007 Award Solutions, Inc. All rights reserved. No part of this book shall be reproduced or transmitted by any means, electronic, mechanical, photocopying, recording or otherwise, without the express written consent from Award Solutions, Inc.
2100 Lakeside Blvd. Suite 300 Richardson, Texas 75082 Phone: +1.972.664.0727 Fax: +1.972.664.0729 If you have any questions, concerns or comments regarding this course please write to us at: www.awardsolutions.com [email protected]
by training with those who already are
expertbecome
an
2100 Lakeside Blvd. Suite 300 Richardson, TX 75082 1.877.47.Award [email protected]
Award Solutions, Inc. is a knowledge-based company rooted in the areas of advanced wire-less and Internet technologies. Award’s areas of expertise include:
• WiMAX & Emerging Trends • Wireless Fundamentals • CDMA2000 - 1x and 1xEV-DO • GSM and GPRS • UMTS (W-CDMA) • IP, VoIP & IMS
Training Services
Award Solutions offers technical courses in wireless technologies and data communica-tions. Our courses range from introductory to advanced levels brimming with technical details.
The level of technical depth in our advanced technology training courses is unique to the marketplace. Award is known for teaching “beyond the facts” – we bring you the big picture view, and explain the hows and the whys, along with the factual details.
Overview of Services
Network Performance ServicesAward Solutions offers various services to help you in the area of network performance.
Training Solutions - Award Solutions brings together technology theory explained in class-rooms with their practical applications in a hands-on environment through Performance Workshops.
Some examples of Performance Workshop topics include: • 1x Radio Networks Performance • 1xEV-DO (Rev 0) Performance • AMR Performance • GSM Performance • GPRS and EDGE Performance • UMTS (W-CDMA) Performance
Network Solutions - Award believes in going beyond consulting to provide complete solu-tions to your network performance issues.
Some examples of services include: • Business Planning • Network Planning and Design • Network Performance and Optimization • Performance Benchmarking • Acceptance Testing
Customized Solutions
Award Solutions will be happy to customize our course content to meet your specific needs. We can integrate topics across our courses to deliver a custom “bootcamp” to cover only the information important to you and your team. These bootcamps are designed to help teams ramp up on new technologies quickly.
We offer a multitude of delivery methods:
Instructor led onsite training. Our instruc-tors travel to your facility to engage the stu-dents in an interactive learning experience.
Instructor led virtual classroom train-ing. Our instructors deliver our training courses over the Internet using web-based mul-timedia tools.
Performance Workshops. This offers a mix of classroom training and hands-on application of concepts learned in class.
Self-paced eLearning. Our eLearning courses enhance the learning experience using the full multimedia medium, rich with anima-tions, interactions and review questions.
Lunch & Learn. These short seminars help your team quickly learn the highlights of tech-nologies you choose from our curricula.
Webinar. A compact overview of current tech-nologies. Instructor led, and typically no longer than 90 minutes, they are delivered via the web.
expertbecome
an
by training with those who already are
2100 Lakeside Blvd. Suite 300 Richardson, TX 75082 1.877.47.Award [email protected]
Instructor led Courses
Emerging Trends
WiMAX Essentials
Exploring WiMAX
4G Technology Overview
Wireless Fundamentals
Wireless and 3G Basics
Wireless Technologies and Networks Overview
3G Comparative Overview
1x & 1xEV-DO
Exploring CDMA2000 (1x) Networks
Mastering CDMA2000 (1x) Call Processing
1x Radio Networks Performance Workshop
1xEV-DO Essentials
Mastering 1xEV-DO Radio Networks (Rev 0)
Mastering 1xEV-DO Radio Networks (Rev A)
Mastering 1xEV-DO Radio Networks (Rev 0 & Rev A)
Mastering 1xEV-DO Signaling (Rev 0)
Mastering 1xEV-DO Signaling (Rev 0 & Rev A)
1xEV-DO (Rev 0) Performance Workshop
Mastering 1xEV-DO (Rev C)
Mobile IP in 1x/1xEV-DO Networks
MMD (IMS) in 1x/1xEV-DO Networks
1x & 1xEV-DO (continued)
VoIP and SIP in 1x/1xEV-DO MMD Networks
Wireless Internet - From IP to 1xEV-
DO
GSM & GPRS/EDGE
Exploring GSM
GSM Performance Workshop
AMR Performance Workshop
Exploring GPRS and EDGE
Mastering GPRS and EDGE
GPRS and EDGE Performance Workshop
Wireless Internet - From IP to GPRS/EDGE and UMTS
UMTS (WCDMA)
UMTS Essentials
Exploring UMTS (WCDMA)
Mastering UMTS (WCDMA) Radio Networks
Mastering UMTS (R99) Signaling
UMTS (WCDMA) Performance Workshop
Mastering HSDPA
Mastering HSUPA
Mastering HSDPA/HSUPA Signaling
Mastering UMTS-LTE
IMS in UMTS Networks
Mastering UMTS Core Networks R4 & R5 (IMS)
UMTS (WCDMA) (continued)
Wireless Internet - From IP to GPRS/EDGE and UMTS
WiMAX
WiMAX Essentials
Exploring WiMAX
Mastering WiMAX Signaling
IP, VoIP & IMS
Internet Fundamentals for 3G
Exploring IPv6 for Wireless Networks
Exploring Voice over IP for Wireless Networks
Mastering SIP for Wireless Networks
IMS in UMTS Networks
MMD (IMS) in 1x/1xEV-DO Networks
VoIP and SIP in 1x/1xEV-DO MMD Networks
Instructor led Onsite Training
Instructor led Virtual Classroom Training
by training with those who already are
expertbecome
an
2100 Lakeside Blvd. Suite 300 Richardson, TX 75082 1.877.47.Award [email protected]
Emerging Trends
Overview of OFDM
Overview of WiMAX
Wireless Fundamentals
Overview of 3G Wireless Networks
WAP 2.0 and M-Services
Overview of Wireless LAN
1x & 1xEV-DO
Overview of CDMA2000 Networks
CDMA2000 Air Interface
CDMA2000 Packet Data Networks
Mobile IP for CDMA2000
1xEV-DO Networks (Rev 0)
1xEV-DO Networks (Rev A)
Overview of MMD (IMS) in 1x/1xEV-DO Networks
GSM & GPRS/EDGE
Overview of GPRS
GPRS Air Interface
GPRS Packet Data Operations
GPRS Mobility
UMTS (WCDMA)
Evolution from GSM to UMTS
Overview of UMTS
UMTS/WCDMA Air Interface Fundamentals
UMTS Signaling
GSM & GPRS/EDGE (continued)
UMTS Mobility
HSDPA (R5)
HSUPA (R6)
WiMAX
Overview of OFDM
Overview of WiMAX
IP, VoIP & IMS
Welcome to IP Networking
Overview of MPLS
IP Quality of Service
Session Initiation Protocol
Seamless Mobility
Overview of MMD (IMS) in 1x/1xEV-DO Networks
Self-paced eLearning Courses
Self-paced eLearning
All rights reserved. This course book and the material and information contained in it ("course
material") are owned by Award Solutions, Inc. ("Award"). The course material shall not be
modified, reproduced, disseminated, or transmitted by or in any medium, form, or means,
electronic or mechanical, including photocopying, recording, or any information retrieval
system, in whole or in part, without the prior express written consent of Award. The
unauthorized use, modification, reproduction, dissemination or transmission of the course
material, in whole or in part, is strictly prohibited.
The course material is designed and distributed as instructional aid for courses taught by
Award’s authorized employees and contractors. Award makes no representations or warranties
and disclaims all implied warranties with respect to the information contained herein or products
derived from use of such information and undertakes no obligation to update or otherwise
modify the information or to notify the purchaser or user of any update or obsolescence. Award’s
total liability in connection with the course material is the amount actually received by Award
from the purchaser/user for the purchase of the course material.
Table of Contents
Version 1.0
Table of Contents
HSPA Architecture and Protocols.......................................................1-1
UMTS Basic Data Call Setup .............................................................2-1
HSPA Key Concepts .........................................................................3-1
HSDPA Data Call Setup ....................................................................4-1
HSUPA Data Call Setup ....................................................................5-1
Multi-Services Scenario ....................................................................6-1
HSPA Interworking ..........................................................................7-1
Appendix: HSDPA Call Setup ...........................................................A-1
Acronyms .......................................................................................B-1
References......................................................................................C-1
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
HSPA Architecture HSPA Architecture and Protocolsand Protocols
1-1
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Objectives
1-2
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
ObjectivesObjectivesAfter completing this module, you will be able to:
• Describe the 3GPP release features• Draw the UMTS network architecture and
identify HSPA network impacts• Describe how UMTS separates the core
network’s functions from the radio access network’s functions
• Sketch and describe the UMTS radio access protocol stack, RRC, RLC, MAC and PHY
• Describe the protocol view with HSPA features • Identify different types of MAC protocols used
in HSPA
1-3
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
UMTS Release 99
• 2 Mbps theoretical peak packet data rates
• 384 kbps (practical)
UMTS Release 4
• MSC Server-based architecture
• Bearer Independent Call Control (CS)
UMTS Release 5
• HSDPA (14 Mbps downlink theoretical)
• IMS (IP Multimedia Subsystem for multimedia)
UMTS Release 6
• HSUPA (up to 5.76 Mbps uplink)
• MBMS (Multimedia Broadcast Multicast Service)
UMTS Release 7
• Multiple Input Multiple Output (MIMO) Antenna Systems in combination with Orthogonal
Frequency Division Multiplexing (OFDM)
UMTS Release 8
• LTE is an important work item in the 3GPP standards that concerns the Long Term Evolution
(LTE) of UMTS. LTE brings radical changes to the air interface as well as the network
architecture.
HSPA is a non-standard generic term that is often used to refer to both the uplink (HSUPA) and downlink
(HSDPA) high-speed packet technologies in 3GPP.
HSPA in a UMTS Roadmap
1-4
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Release 4Bearer-independent CS architecture
Release 99Voice,2 Mbps data rate
Release 5HSDPA (14 Mbps DL),IP multimedia subsystem
R 7
Release 6HSUPA(5.76 Mbps UL),MBMS
Release 7OFDM/MIMO
HSPA in a UMTS RoadmapHSPA in a UMTS Roadmap
Frozen!(completed)
R 5R 6R 4
HSPA = HSDPA + HSUPA
R 8
Release 8LTE
R 99
1-5
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
3G Universal Mobile Telecommunications System (UMTS) networks are shown in the adjoining slide.
UMTS specifies a Core Network (CN) architecture and services to be offered on this CN. The UMTS
Terrestrial Radio Access Network (UTRAN) defines the radio access interface to land mobiles.
The UMTS CN is defined in a modular fashion and is completely independent of radio access
technologies. It specifies the Iu interface, which can be used by different Radio Access Networks (RANs)
to connect to the UMTS CN.
The figure shows a typical UMTS architecture where the CS and PS domains are supported by separate
physical entities. The CS domain is supported by an evolved 2G MSC/VLR, whereas the PS domain is
supported by an evolved 2G SGSN. Both the CS and PS domains support their own state machine. The
User Equipment (UE) maintains two separate state machines—one for the CS domain and one for the PS
domain.
The UTRAN maintains two Iu connections to the two different domains. The UTRAN provides one
unified set of radio bearers for both the PS domain and the CS domain. These radio bearers carry bursty
traffic for the packet domain and traditional telephony traffic for the CS domain. The UTRAN provides
the distribution functionality to the two domains.
The Home Location Register (HLR) is shared between the two domains. The HLR maintains a common
subscription database for both domains. However, it maintains separate location information for the two
domains.
The Impact of the Release 5 and Release 6 features for High Speed Packet Access (HSPA) are mainly in
the UTRAN and the UE. The Packet Switched Core Network (PS-CN) is impacted as well, but to a lesser
degree. The transport infrastructure also needs improvement in performance since larger amounts of data
have to be transported between the Radio Access Network (RAN) and the CN. This backhaul
improvement may be done gradually according to the requirements of the network operator as the volume
of HSPA traffic increases with time.
UMTS Network and HSPA
1-6
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
UMTS Network and HSPAUMTS Network and HSPA
Packet-Switched
Circuit-SwitchedHLR
3G MSC/VLR
MSC
3G-SGSNGGSN
GGSN
UTRAN
AuC
3G-SGSN
IP
SS7
IntraPLMN IP
Back bone
UE RNCNode B
MajorHSPA impact
MajorHSPA impact
Minor HSPA impact
Gradual capacity improvements
No impact
Uu
Iub
Iu-cs Iu-ps
RNC
Iur
1-7
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
The Access Stratum (AS) provides services related to the transmission of data over the radio interface and
the management of the radio interface to the other parts of UMTS.
The AS includes the following protocols:
• UE - Access Network: This protocol supports the transfer of detailed radio-related information to
coordinate the use of radio resources between the UE and the access network.
• Access Network - Core Network/Serving Network: This protocol supports the access from the
Core Network/Serving Network to the resources provided by the access network. It is independent
of the specific radio structure of the access network.
Non-Access Stratum (NAS) is a logical separation of the Core Network and Services Network from the
AS. This pertains to various functions used to provide services such as mobility management, location
management, security, etc. to the user in the UE.
It is important to note that NAS messages can transparently flow from the UE (through the access
network) to its peer entities in the Core Network (CN) or services network. Another key aspect is that the
UE contains both AS and NAS personalities, and together they provide the ability for the UE to obtain
both access and services. Based on the principles of Access Stratum (AS) and Non-Access Stratum
(NAS), the signaling protocols can be divided into access and non-access signaling protocols. These
signaling protocols are implemented between the UE and the UMTS network. To establish services, the
UE must invoke both access and non-access signaling procedures.
The access signaling procedures are invoked to set up, reconfigure and release radio bearers. These
procedures are related to the establishment of a radio connection from the UE all the way to the CNs. This
includes signaling to establish radio channels over the air, signaling to establish Iub user plane connections
within the radio network, and Iu signaling to establish Iu user plane connections between the UTRAN and
CNs.
A good illustration of the benefits of the separation of NAS vs. AS protocols is the HSPA technology. As
an air-interface solution, this technology does not imply any major changes with respect to the NAS when
the AS is modified.
Access and Non-Access Layers
1-8
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Access and NonAccess and Non--Access LayersAccess Layers
Application-related Signaling(Voicemail, HTTP, email, etc.)
Service setup-related Signaling(GSM, GPRS or UMTS)
Radio-related Signaling
Node B
SGSN/GGSN
MSCUE
PSTN
Internet
Iu
Iu
RNC
Radio Connection
Non-AccessStratum
AccessStratum
Minimal HSPA
Impact
Major
HSPA
Impact
1-9
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
The packet signaling protocol reference model and packet traffic protocol reference model are shown as
illustration only. They are included as reference for the students to understand where the radio interface
protocols fit in.
The signaling user plane consists of the following functional components:
UE: This is the mobile and it contains the radio interface protocols as well as the Core Network
(CN) signaling protocols, Session Management (SM) and Packet Mobility Management
(PMM). These layers work together to provide the signaling required to run applications.
UTRAN: The Node B and RNC are simplified here as the UTRAN and the general protocol model
from a mobile’s perspective without any of the transport layer protocols.
3G-SGSN: This illustrates the use of the RANAP protocol for signaling on the Iu – the PS interface
and the GPRS Tunneling Protocol (GTP-C) control protocol used for tunnel establishment.
3G:GGSN: At the GGSN, the same signaling protocol, GTP-C, is used, and it runs on top of the
UDP/IP. Also, the GGSN can talk to the Internet and can use any L1 or L2 mechanisms.
Packet Signaling Protocol Reference Model
1-10
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Packet Signaling Protocol Packet Signaling Protocol Reference ModelReference Model
PMM /SM
RRC
RLC
MAC
UMTS RF UMTS RFL1
UEUu
UTRANIu-PS
3G-SGSN
L1
RRC RANAP
RLC
MAC
AAL5/ATM
Signaling Bearer
PMM / SM
RANAP
AAL5/ATM
Signaling Bearer
SCCP SCCP
GGSN
L1
E.g., IP, PPP, OSP
GTP-C
L2
UDP/IP
L1
GTP-C
L2
UDP/IP
RRC
Relay
Radio Interface Protocols
1-11
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
The specific air interface protocol layer changes are summarized in this figure. There are primarily three
layers in the UMTS R99 air interface architecture.
• Layer 1 is the physical layer responsible for over-the-air functions such as spreading and
modulation.
• Layer 2 consists of the Medium Access Control (MAC) and Radio Link Control (RLC) layers. The
MAC layer handles system access operations and the RLC layer provides reliable delivery of user
traffic.
• The third layer is the Radio Resource Control (RRC) layer which is the brains of the RNC. The
RRC layer is responsible for all signaling and messaging to the UE.
The key enhancements to the air interface protocol layer architecture are the enhanced dedicated channel
(E-DCH) related functionalities, primarily at the MAC and physical layers. This enhanced channel enables
superior packet data performance in the uplink. The E-DCH control function is responsible for controlling
operations of the new channels introduced in HSUPA systems to handle packet data services. Changes to
the RRC are required so that E-DCH-related information can be communicated to the UE.
Protocol Changes for HSPA
1-12
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Signaling Data
Radio Link Control (RLC)
Media Access Control (MAC)
Physical Layer
LinkLayer
PhysicalLayer
UpperLayers
Radio Resource Control (RRC)
L3
Supports new HSPA channelsand modulation
Protocol Changes for HSPAProtocol Changes for HSPA
Modified to manage
HARQ and HSPA process
UTR
AN
L2
L1
PDCP
Packet Data Convergence Protocol (PDCP)
User DataCS PS
Modified to support
HSPA call setup and
QoS
No Change
1-13
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
As indicated in the protocol stack for the control plane, the Radio Resource Control (RRC) protocol,
residing in the UE and the Serving RNC, is by far the most important signaling protocol for UE-UTRAN
signaling. One can say that the RRC is the master of the UTRAN, because we have all UE-UTRAN layer
3 signaling messaging at this layer, and it is also fully in charge of the lower layers (i.e., Radio Link
Control (RLC), Medium Access Control (MAC) and the Physical Layer). The latter means that the lower
layers always report conditions and states to the RRC, and the RRC can always, if needed, make changes
for the setting of lower layers.
On the UE side, this is done completely internally since all the above mentioned protocol layers reside in
the terminal. On the network side, the RRC, RLC and MAC reside in the RNC. However, since the
physical layer is at the Node B, the RRC-physical layer communication takes place over the Iub interface.
Radio Resource Control: RRC
1-14
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Radio Resource Control: RRCRadio Resource Control: RRC• Master of UTRAN
– UE control: All UE UTRAN messages are at the RRC layer
– Lower layers control
RRC
RLC
MAC
PHY
1-15
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Some of the functions performed by the Radio Link Control (RLC) layer are:
• Segmentation and Reassembly: Variable length Protocol Data Units (PDU) are segmented and
reassembled into and from smaller RLC Payload Units (PU). One RLC PDU may carry one PU or
several PDUs when the header is compressed. The minimum transmission size depends on the
smallest possible bit rate.
• Error Correction: In the acknowledged mode, the RLC layer provides error correction. The RLC
provides retransmission by:
– Selective Repeat
– Go Back N
– Stop-and-Wait Automatic Repeat Request (ARQ)
• In-sequence Delivery of Higher Layer PDUs: In the acknowledged mode, the RLC layer
preserves the order in which the higher layer PDUs were submitted. If the order of higher layer
PDUs is not desired, the out-of-sequence delivery is done using the other data transfer services.
• Transfer of User Data: The RLC provides three types of data transfer services to users of RLC
services:
− Transparent mode
− Unacknowledged mode
− Acknowledged mode
• Notification of Unrecoverable Errors If the RLC cannot resolve any errors using exception-
handling procedures, it notifies the upper layers about the errors.
Radio Link Control: RLC
1-16
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Radio Link Control: RLCRadio Link Control: RLC
Functions
Notifies Upper Layers of
Unrecoverable Errors
Supports Automatic
Repeat Request (ARQ)
In-sequence Delivery of
Higher Layer PDUs
Error Correction
Segmentation and
Reassembly
Ciphering(AM and UM)
3 modes of operation
AM, UM, TM
1-17
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
• Ciphering RLC provides protection against unauthorized acquisition of data. Ciphering is done
either in the RLC or MAC layer depending on the type of RLC data (i.e., transparent or non-
transparent).
• QoS setting The QoS level can be set by the RRC. This affects how the retransmission protocol
will be used to correct errors that have been detected.
Radio Link Control: RLC (continued)
1-18
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Radio Link Control: RLC Radio Link Control: RLC (continued)(continued)
Functions
Notifies Upper Layers of
Unrecoverable Errors
Supports Automatic
Repeat Request (ARQ)
In-sequence Delivery of
Higher Layer PDUs
Error Correction
Segmentation and
Reassembly
Ciphering(AM and UM)
3 modes of operation
AM, UM, TM
1-19
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
The Medium Access Control (MAC) protocol provides its services to the higher layers in the form of
logical channels, characterized by the type of information that is being sent on them. The MAC provides
its services to both the control plane and user plane.
Since the logical channels and transport channels exist above and below the MAC layer, it is quite natural
that the multiplexing of the logical into transport channels becomes a fundamental function for the MAC.
In the MAC layer, logical channels are mapped to transport channels according to the Transport Formats
(TFs). The MAC can also schedule and prioritize the resources (e.g., on the common channels) between
the UEs and between data flows.
When common transport channels are used, the UE ID is added and read by the MAC layer. In case the
RLC protocol is operating in the transparent mode and the ciphering procedure is on, ciphering occurs at
the MAC layer since there is no RLC header, and, hence, no sequence number.
Medium Access Control: MAC
1-20
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Medium Access Control: MACMedium Access Control: MAC
Functions
Logical to Transport CH Multiplexing
TrCH Type Switching
Selection of Appropriate TF for Each
TrCH
Priority HandlingIdentification
of UEs on Common
TrCHs
Ciphering (if TM-RLC)
1-21
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
The Medium Access Control – High Speed (MAC-hs) entities handle HSDPA traffic in the UTRAN. For
each HSDPA UE, there is one MAC-d entity controlling its traffic. In addition, the MAC-d entity is
associated with a MAC-hs in the Node B. The transport blocks are sent from the MAC-d (in the RNC) to
the MAC-hs (in the Node B) using the HS-DSCH framing protocol on the user plane. These messages
may also carry inband signaling for each UE.
For HSUPA, the Node B is enhanced with the MAC-es entity. For each UE there is a MAC-e entity at the
Node B. This MAC protocol is responsible for the scheduling of resources for the UE as well as the
Hybrid-ARQ related processes. The MAC-e does the demultiplexing of MAC-e PDUs. At the RNC, the
MAC-es is responsible for receiving the MAC-e PDUs and reordering them according to a sequence
number. The MAC-es at the RNC is also responsible for macro-diversity processing that is needed as a
result of the uplink soft-handover. The MAC-es only resides at the S-RNC (serving RNC), which manages
radio resources for the UE.
MAC Changes in UTRAN
1-22
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
MAC-esMAC-esMAC-es
MAC-eMAC-eMAC-e MAC-hs
MAC-d
MAC Changes in UTRANMAC Changes in UTRAN
TransportChannels
MAC-dMAC-d
Iub
Logical Channels
RNC
TransportChannels
MAC-c/sh
Node BFraming Protocol
1-23
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
The functions of Medium Access Control – High Speed (MAC-hs) include:
• Multiplexes/Demultiplexes data to and from HS-PDSCH Channels: The MAC-hs receives
transport blocks for all UEs that have been assigned to the HS-DSCHs. The MAC-hs then
decides who receives data and on which HS-PDSCH.
• Handles the priority of data between UEs: The MAC handles the priority of data to different
UEs using a dynamic scheduling mechanism.
• Selects Modulation and number of spreading factors: The size of the data sent in one frame is
determined by the available modulation scheme. This is based on the channel conditions and the
number of available spreading factors based on the other traffic in the cell.
• Data transfer: The MAC-hs provides peer-to-peer transfer of MAC Service Data Units (SDU).
The MAC-hs also uses the Hybrid ARQ incremental redundancy scheme to send the data to the UE
and send the retransmission based on feedback from the UE.
MAC-hs Functions
1-24
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
MACMAC--hs Functionshs Functions• Multiplexes/Demultiplexes data to and from HS-PDSCH
channels• Handles the priority of data between UEs• Selects modulation and number of spreading factors• Data transfer
– Uses Hybrid ARQ to transfer data to the UE– Performs incremental redundancy based on the feedback from
the UE
TransportChannels
LogicalChannels
MAC Control
MAC-d
MAC Control
MAC – High SpeedMAC-hs
1-25
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
The MAC layer undergoes significant changes to support the HSUPA feature. The changes required at
various entities in a UMTS system are outlined below:
• UE Enhancement: The UE implements a new MAC entity that resides between the existing
MAC-d layer and the physical layer. This entity carries out the functions of the MAC-es and
MAC-e. The standard does not distinguish between these two sublayers at the UE. The MAC-e/es
entity takes care of (i) HARQ retransmissions, (ii) multiplexing of multiple MAC-d PDUs into a
single MAC-e PDU for the physical layer processing, and (iii) E-TFC selection (effectively, the
uplink data rate) based on the UTRAN instructions.
• Node B Modifications: The Node B requires a new MAC-e entity so that tasks related to
processing schedule requests from the UE and scheduling uplink resources, HARQ retransmissions
and E-DCH demultiplexing can be performed. The cells in the E-DCH active set influence the data
rate selection process executed by the UE.
• RNC Changes: The MAC-es is added to the RNC’s MAC layer so that selection combining of
uplink packets can be carried out and the in-sequence delivery of packets can be ensured.
The Transport Network Layer (TNL) helps transport information from one network entity to another. The
E-DCH Framing Protocol (FP) facilitates carrying of the information associated with the E-DCH.
E-DCH Protocol Architecture
1-26
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
EE--DCH Protocol ArchitectureDCH Protocol Architecture
PHY
MAC-e /MAC-es
MAC-d
PHY
MAC-e EDCH FP
Node B SRNCUE Uu Iub+Iur
DTCH DCCH DTCH DCCH
MAC-d
E-DCHFP
MAC-es
• HARQ• Multiplexing to
form MAC-e / MAC-es
• Rate selection
• Scheduling request processing
• Scheduling• HARQ• MAC-e Demux
• MAC-es disassembly
• Macro diversity selection combining
• Reordering
1-27
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
MAC-e Entity:
• A UE-specific MAC-e entity instance is created to handle E-DCH traffic from each UE at its
serving cell Node B
• A MAC-e PDU is the E-DCH-specific PDU for the current transmission
• A MAC-e PDU may consist of MAC-es PDUs from multiple flows
• A MAC-e PDU may also contain UE-specific schedule information
• The composition of a MAC-e PDU changes from one E-DCH transmission to the next since it is a
combination of data from multiple flows
• A Node B MAC-e entity demultiplexes the PDU sent by a UE
• A MAC-e PDU header should contain information about the contained MAC-es PDUs. The header
information assists the Node B in demultiplexing and retrieving schedule information, if included.
MAC-es:
• A MAC-es processing instance is created per the UE at the Serving RNC (SRNC)
• A MAC-es PDU is made up of MAC-d PDUs from a single flow
• The MAC-d PDUs included in a MAC-es PDU are sent as part of the MAC-e header information
• A MAC-es PDU header includes a Transmission Sequence Number (TSN) to assist with
resequencing of MAC-d PDUs for delivery at the SRNC. The SRNC may receive MAC-es PDUs
out of order due to the Hybrid ARQ. The MAC-es entity at the SRNC is responsible for the
reordering function.
What are MAC-e and MAC-es?
1-28
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
What are MACWhat are MAC--e and MACe and MAC--es?es?MAC-e
• One instance per UE at the Node B• Responsible for demux at the Node B• May contain MAC-es PDUs from multiple MAC
flows• Schedule information handler at the Node B
MAC-es• One instance per UE at the Serving RNC (SRNC)• Handles selection combining in case of macro
diversity• Responsible for MAC-es disassembly and
reordering
1-29
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
The UTRAN radio interface defines an elaborate channel structure for communication between different
layers. Each layer provides a set of channels through which upper layers can transfer information
(signaling and traffic). The radio interface layers define the following three types of radio channels:
• Physical channels: The physical channels are the interface between the UE and the UTRAN,
representing an over-the-air interface. Each physical channel is identified by a specific
channelization code. The physical channels specify how the data is transmitted over the air.
Physical channels are carried in 10 or 2 ms frames.
• Transport channels: Transport channels are the services provided by the physical layer to the
upper layers. A transport channel specifies how and with what characteristics upper layer
information is transmitted over the air. For example, if the user is on a simultaneous voice and data
call, voice and data traffic can be sent over different transport channels. Each application has
different requirements. Data might need higher protection than voice. Therefore, different transport
channels specify different protection schemes to transport user traffic. Transport channels are
mapped to physical channels, and transport channel frames are known as transport blocks.
Transport blocks can be 10, 20, 40 or 80 ms in length.
• Logical channels: Logical channels are the interface between the MAC and the RLC layer. The
logical channel is concerned with the type of data is transmitted, and logical channels understand
whether voice, signaling and data traffic is being sent. Each logical channel corresponds to one
RLC instance. The logical channels are mapped to transport channels, and logical channel frames
are the same size as corresponding transport channel blocks.
When a radio bearer is set up for a UE, all three types of channels have to be configured. For example, a
radio bearer for voice applications may have three logical and three transport channels to support different
classes of bits. However, all three transport channels are mapped to the same physical channel.
Radio Protocols and Channels
1-30
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Radio Protocols and ChannelsRadio Protocols and Channels
Control Plane Signaling User Plane Information
Non-Access Stratum (NAS)
Access Stratum (AS)
Packet and Circuit CN Signaling data voice
PDCPRRC
MAC
voicedata
Logical Channels
Transport Channels
Physical Channels
RLC
PHY
1-31
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
HSDPA is an evolution from UMTS R99. Hence, HSDPA supports all the UMTS R99 configurations
without any restrictions. HSDPA also introduces new channels specifically designed to support high-speed
packet data services. These channels are:
1. High Speed – Downlink Shared Channel (HS-DSCH): The HS-DSCH is a new channel
designed to carry high-speed packet data traffic. Each cell may support one or more HS-DSCHs.
The HS-DSCH is a shared channel shared across all users requesting HSDPA specific high-speed
packet data services. Sharing of the HS-DSCH is based on Time-Division Multiplexing (TDM)
across multiple users.
2. High Speed - Shared Control Channel (HS-SCCH): The SCCH is a control channel associated
with the HS-DSCH. The SCCH conveys the HS-DSCH allocation information including the user
identity, the number of spreading factors used, and the modulation scheme.
3. High Speed - Dedicated Physical Control Channel (HS-DPCCH): The HSDPA system gathers
current radio condition information on a continuous basis from all the mobiles vying for access to
the HS-DSCH. Each UE measures and determines the C/I value of each active set pilot and report
the C/I of the best sector. Since HSDPA systems support the Hybrid ARQ scheme, the transmitter
(Node B) transmits some of the turbo-encoded symbols first and waits for a physical layer
acknowledgement from the receiver (UE). If the response is a NACK, the base station continues to
send additional symbols. If the response is an ACK, the base station stops sending the remaining
symbols and continues with the next packet. The mobile sends these ACK/NAK commands along
with the current CQI on the HS-DPCCH.
HSDPA Channels
1-32
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
HSDPA ChannelsHSDPA Channels
HS-DSCH (Transport Channel)/
HS-PDSCH(Physical Channel)
HS–DPCCH(PhysicalChannel)
New HSDPA Channels
Downlink
HS-SCCH(Physical Channel)
Uplink
1-33
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
High Speed Uplink Packet Access (HSUPA) introduces new channels to support uplink high speed packet
data services. The main channel of interest is the Enhanced Dedicated Channel (E-DCH), a transport
channel. In addition, other associated channels, primarily physical channels, enable high speed data
services on the uplink. These channels and their functions are described below:
1. Enhanced Dedicated Channel (E-DCH): The E-DCH is an uplink transport channel defined for
HSUPA. The E-DCH carries user traffic from the UE to the Node B on the uplink. An E-DCH
transport channel may be mapped to one or more physical channels as required. To achieve high
data rates while maintaining reverse link load at a manageable level, the E-DCH is controlled by
the Node B.
2. Enhanced Dedicated Physical Data Channel (E-DPDCH): The E-DPDCH carries E-DCH user
traffic from the UE on the uplink. Since the E-DPDCH is on the uplink, the channelization codes
are used to separate channels within a given UE. This allows HSUPA to use very short codes
(e.g., 2-bit or 4-bit codes) to send user data.
3. Enhanced Dedicated Physical Control Channel (E-DPCCH): The UE determines the rate of
transmission and associated transmission characteristics on the E-DCH. The E-DPCCH is an
uplink physical channel used to convey E-DPDCH transmission characteristics. The E-DPCCH
carries only physical layer control information related to the E-DPDCH.
4. E-DCH Hybrid ARQ acknowledgement Indicator Channel (E-HICH): The E-HICH is a
physical channel that carries information related to Hybrid ARQ. This downlink channel is used
by the Node B to convey a positive or negative acknowledgement (ACK/NACK) for a physical
layer packet received from a UE at the Node B.
HSUPA-Related Channels
1-34
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
HSUPAHSUPA--Related ChannelsRelated Channels
E-DPCCH(1)
Downlink
E-DCH
E-DPDCH(1 or more)E-AGCH E-RGCH E-HICH
Uplink
Transport
Physical
HSUPA Channels
1-35
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
5. E-DCH Absolute Grant Channel (E-AGCH): The E-AGCH is a physical channel used by the
Node B to convey absolute power ratio allocation for uplink E-DCH transmission.
6. E-DCH Relative Grant Channel (E-RGCH): The E-RGCH conveys power allocation for uplink
E-DCH transmission by the Node B. The E-RGCH conveys corrections to already communicated
serving grants, which is different from the absolute power allocation grants conveyed using the E-
AGCH channel.
It should be noted that there is only one transport channel in this set. All other channels exist only as
physical channels.
HSUPA-Related Channels (continued)
1-36
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
HSUPAHSUPA--Related Channels Related Channels (continued)(continued)
E-DPCCH(1)
Downlink
E-DCH
E-DPDCH(1 or more)E-AGCH E-RGCH E-HICH
Uplink
Transport
Physical
HSUPA Channels
1-37
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Summary
1-38
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
SummarySummary• HSPA is an enhancement in Release 5 & 6 of UMTS
specifications• HSPA technology has a significant impact on the UE-
UTRAN protocols• The PHY, MAC and the RRC layers are enhanced• For HSDPA, a new MAC-hs protocol is implemented at
the Node B• For HSUPA, the MAC-e protocol is implemented at the
Node B and a MAC-es is implemented at the RNC• The UE protocol stack is also impacted• New Transport and Physical channels are defined for
HSPA operations
1-39
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Review Questions
1-40
Mastering HSDPA/HSUPA Signaling
HSPA Architecture and Protocols
Review QuestionsReview Questions1. In what UMTS specification release do we first see HSUPA?2. What are the two main strata in UMTS called and what is their
difference?3. Name the air interface protocols of the UTRAN in order, assign a layer
number to each and place each protocol in the corresponding node.4. Which protocol(s) is not impacted by the HSPA operations?5. Which protocol needs to be implemented at the Node B for high-speed
downlink data transmissions?6. What new protocol needs to be implemented at the RNC for high-speed
uplink operations?7. In simple terms, describe the role of the framing protocol in HSPA
operations.8. Name all new channels needed for HSPA operations. What type(s) of
channel are these (Logical, Transport, Physical)?
1-41
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
UMTS Basic Data UMTS Basic Data Call SetupCall Setup
2-1
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Objectives
2-2
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
ObjectivesObjectivesAfter completing this module, you will be able to:
• Explain how packet sessions are activated• Describe the actions of the radio network components
in a packet session• Discuss how Quality of Service (QoS) is established for
a packet session• Examine the roles of the MAC and RLC layers in a
packet session
2-3
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
To set up a PS connection in UMTS, the UE and the Network must go through a well-defined set of
procedures.
The procedure begins by the UE sending a request for necessary radio resources to start the call setup.
This procedure has to be initiated by the UE even in the case of an incoming call. As a result of this
request, we have to establish a signaling link between the UTRAN and Core Network (CN) as well. The
network must start the authentication procedures with the UE at this point and may carry out other
optional security related procedures. After passing the security procedures, the UE informs the CN about
the type of call and the specifics of the Quality of Service (QoS) required for the service. After this
specific request for a QoS is sent by the UE, the CN and the UTRAN negotiate an appropriate QoS that
may be granted to the UE, taking into account many factors like the subscriber profile and the cell load,
for example. Once the QoS level has been decided by the network, the UE must be informed and
configured with all the necessary parameters to set up a Radio Access Bearer (RAB). A RAB defines
exactly all the resources allocated to the mobile for a given service type. The final result of these
procedures is an established session (or circuit) with a well-defined QoS. It is important to take note that in
UMTS the QoS is more than just throughput and delay, although these are still among the most important
QoS parameters.
UMTS End-to-End View
2-4
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
UMTS EndUMTS End--toto--End ViewEnd View
Node BPS-CN
Iub IuUu
UE
End-to-End QoS
Radio Resources Iu connection
QoS Negotiation
Security-Related Procedures
Request for a QoS
RAB Setup
UTRAN
RNC
2-5
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
The RRC has two modes of operation: Idle mode and Connected mode. In idle mode, no signaling
connection exists between the UE and the UTRAN. When the UE is in the connected mode, user data may
be sent.
When the UE is powered on, it enters idle mode where it attempts to access a Public Land Mobile
Network (PLMN). It selects a cell that is able to provide available services, and tunes to its control
channel. This is known as “camping on a cell.” The process continues with a location registration
procedure. This effectively makes the UE known in the network. The UE continually monitors
neighboring cells to see if another cell is more suitable. This is particularly useful as the UE moves
throughout the network.
There are several reasons for a UE to “camp on a cell”:
• It enables the UE to receive system information from the PLMN
• The process of initiating a call is simpler, because the UE has already chosen a cell
• The UE is ready to accept incoming calls. The UE is notified of an incoming call via the control
channel to which the UE continues to listen.
• While idle, the UE is able to conserve battery consumption by sleeping and only waking up
periodically to check for incoming messages
The second mode of operation is the connected mode. In this mode, one and only one signaling connection
exists between the UE and the Radio Network Controller (RNC) – the RRC connection. In this mode, the
UE is assigned a Radio Network Temporary Identity (RNTI), which is used to identify the UE on common
transport channels. In addition, the UE is known at either the cell level or the UTRAN Registration Area
(URA) level (i.e., a set of cells). Depending on the state of the UE connection, different mechanisms are
used to communicate with the UE. Mobility procedures are also available in connected mode. These
include Cell/URA updates and handovers.
It is important to note that no radio resources are assigned to the UE when it is in idle mode. In contrast,
while the UE is in connected mode, there may be radio resources assigned.
RRC States
2-6
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
RRC StatesRRC States
Camping on a UTRAN cellIDLE MODE
Release RRCConnection
Establish RRCConnection
Release RRCConnection
Establish RRCConnection
UTRAN Connected Mode
URA_PCH Cell_PCH
Cell_DCH Cell_FACH
HSPA data transmission
2-7
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
For HSPA operation, the RRC model as described above is completely valid. An HSPA-active mobile is
in the CELL_DCH mode during transmission and reception of data using the associated channels. Note
that for HSDPA, the downlink channel is in reality a fully shared channel, although we still call the RRC
state CELL_DCH. The UE still needs to be assigned dedicated channels for uplink power control and use
uplink dedicated channel(s) for transmission to the network. When the UE becomes inactive for a period
of time, the RNC can decide to put the mobile in CELL_PCH or URA_PCH states, where the UE updates
the RNC with its most current cell location.
RRC States (continued)
2-8
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
RRC States RRC States (continued)(continued)
Camping on a UTRAN cellIDLE MODE
Release RRCConnection
Establish RRCConnection
Release RRCConnection
Establish RRCConnection
UTRAN Connected Mode
URA_PCH Cell_PCH
Cell_DCH Cell_FACH
HSPA data transmission
2-9
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
This is a key figure that explains, at a high level, the steps that a mobile (denoted as UE from here on) and
the corresponding network go through when the mobile establishes a packet session.
Two planes are discussed in this module. The control plane is established initially to create a path for
exchanging signaling information needed for service creation.
Once the control plane is established, the user plane is established. In UMTS, the Radio Access Bearer
(RAB) denotes the combination of both the radio bearer (RB) between the UTRAN and the UE, and also
the bearer between the radio and core networks (CN) referred to as the Iu Bearer. In the packet domain,
the Iu bearer is a GPRS Tunneling Protocol (GTP) tunnel. This is an essential component for providing
various types of services with different Quality of Service (QoS). A specific RAB is associated with a
specific QoS to either the circuit- or packet-switched core network.
This concept will be explored in this module.
Data Session Setup Overview
2-10
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
Established at system configuration
Data Session Setup OverviewData Session Setup Overview
Node B
RRC
PS-CN PDN
Iu
Radio Bearer (RB)
ControlPlane
UserPlane
GTP-U
RAB = RB + Iu (GTP) Bearer
Iub IuUu
Physical Channel AAL2 Bearer SIG/AAL5
Physical Channel AAL2 Bearer
Summary of Packet Session
UERNC
2-11
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
Before anything can be done in UMTS, the Radio Resource Control (RRC) connection must be
established. The RRC connection is a logical connection between the UTRAN and the UE, with the
following characteristics:
• Used to identify all UE – UTRAN signaling, whether in the circuit or packet domain
• Only one RRC connection at any time
• Used by the UTRAN to track both the location and state of the user during the life of a call or
packet data session
• The Serving RNC (SRNC) is activated upon establishment of the RRC connection
• All messages sent over this connection are part of the RRC protocol
• The UE is identified with a Radio Network Temporary Identifier (RNTI)
RRC Connection Setup
2-12
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
PS-CN PDNIub Iu
RRC Connection SetupRRC Connection Setup
RNCNode B
RRC
ControlPlane
Uu
Physical Channel AAL2 Bearer SIG/AAL5
RRC Connection Request
RRC Connection Setup
RRC Connection Setup Complete
UE is now known to the SRNC
UE
2-13
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
After the establishment of the RRC Connection, the UE now starts communicating with the Packet
Switched Core Network (PS-CN) by sending the Attach Request message. At this point, the RNC creates
the Iu-Connection by piggy-backing the Attach Request message on a RANAP Initial UE Message. Upon
receiving this message, which is the first message from the UE, the PS-CN likely starts the security
procedures.
Assuming successful outcome of the security procedures, the PS-CN responds to the Attach Request (sent
from the UE) with an Attach Accept. This message normally contains a new P-TMSI number allocated to
the UE. The UE, therefore, acknowledges the reception of the P-TMSI by sending the Attach Complete
message.
Iu Connection Setup Overview
2-14
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
PS-CN PDNIub Iu
Iu Connection Setup OverviewIu Connection Setup Overview
RNCNode B
RRC
ControlPlane
Uu
Physical Channel AAL2 Bearer SIG/AAL5
Initial DT (Attach Request)
Initial UE Message (Att. Req.)
Iu
Signaling connection to UE complete
DT (Attach Accept)
DT (Attach Complete)
Authentication and Security
UE
2-15
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
The control plane has been set up and that is a key requirement so that the UE can proceed with the rest of
the data session setup.
The UE has set up the control plane and now has to set up the data plane. A key component of UMTS is
the Quality of Service (QoS) requested. This affects both the core network (CN) and radio network (RN).
The CN’s primary role is to understand the request for the service and insure that the UE has rights to this
service. The UE may ask for a different QoS than what is subscribed to, and the role of the CN is to check
the subscription information to see if this is allowed. It then passes the request to the RN.
The RN, which may be an independent entity from the CN, obtains the requirements from the CN. It then
performs two key steps:
• Call admission control: The RNC understands the RN limitations, and has to work with the Node
B to ensure that they can handle the load of the new UE together
• Mobile – UTRAN communication: The RNC then establishes the Node B’s radio link and
provides the mobile with the relevant information to initialize the radio interface protocol stack
Data Session Setup
2-16
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
PS-CN PDNIub Iu
Data Session SetupData Session Setup
RNCNode B
RRC
ControlPlane
Uu
Physical Channel AAL2 Bearer SIG/AAL5
IuUplink DT (Activate PDP Context Request)
DT (Activate PDP Context Request)
UE requests QoSPS-CN qualifies QoS
CN/UTRAN enforce QoS
RRC
UE
2-17
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
This figure demonstrates the exchange of information between a mobile (UE) and the CN for a packet
service. Typically, the user subscribes to a certain type of service such as Premium class or Gold class.
These classes have a specific mapping to Quality of Service (QoS) related parameters that the mobile
exchanges with the CN.
The mobile can also choose to request parameters that are different from what it is subscribed to, and the
networks decide if they can allow such a request. In this example, the UE has requested a packet service
with a specific QoS.
Some of the key parameters are shown in this figure such as:
• Class of Service: Interactive class such as a Web service
• Throughput 64 kbps: The expected rate of data transfer of the application
• Delay – 500 ms: Indication how much delay can be tolerated in the system
• Reliability: Indication of the level of reliability needed for this service
Packet Service Request to CN
2-18
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
Packet Service Request to CNPacket Service Request to CN
Packet Switched
Core Network
Quality of Service
UE requests QoS
QoSrequestedby the UE
Reliability10-3 BER
Throughput64 kbps max
Delay500 msec
ClassInteractive
UE
2-19
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
UMTS specifications divide applications and services into four different traffic classes. These
classifications are made based on different characteristics of traffic generated by these applications. The
four traffic classes are described below. HSPA is primarily designed for operation with non-real-time
services like web browsing or downloading of files. Real-time services require further enhancements to
minimize latency, especially for roaming (non-stationary) users.
Conversational class: Speech service is the most well known application of this class. This class is
characterized by stringent low delay and preservation of time relationship (variation) between information
entities of the stream. Although speech is a well-known application of this class, there are other
applications as well. With the advent of Internet and multimedia, new applications such as Voice over IP
(VoIP) and video conferencing tools require a conversational class. Another important characteristic of the
conversational class is that traffic is mostly symmetric.
Streaming class: Real time audio or video is a good example of applications in this class. Streaming is a
technique for transferring data so time relation (variation) between different data elements is maintained.
That is, the delay variation (jitter) should be as minimal possible. The application uses buffering
techniques to smooth delay variation so that the user does not experience any jitter in audio or video.
Streaming does not have requirements of low delay. Streaming applications are asymmetric in nature. The
bandwidth requirement from server to client is much higher than the bandwidth requirement from client to
server.
Interactive class: Web browsing and mCommerce transactions are well known examples of this class.
The class is characterized by a request-response pattern. There is no requirement for maintaining time
relation or low delay. However, overall round trip delay must be within acceptable limits. Reliability is
another important requirement for this class, since any error changes the meaning of transactions.
QoS Classes and HSPA
2-20
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
QoSQoS Classes and HSPAClasses and HSPA
- Background download of emails
- Destination is not expecting the data within a certain time
- Preserve payload content
BackgroundBest Effort
- Web browsing
- Request response pattern
- Preserve payload content
Interactive Class
Best Effort
- Streaming video
- Voice, video callExample of the application
- Preserve time relation (variation) between information entities of the stream
- Preserve time relation between entities of stream
- Conversational pattern (stringent and low delay)
FundamentalCharacteristics
Streaming Class
Real Time
Conversational Class
Real Time
TrafficClass
Initial HSPA usage
2-21
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
Background class: Email retrieval and file transfer are well known examples of this class. There are no
delay or time relation requirement for this class. The destination is not expecting data within a certain
time. The class uses bandwidth when other classes are not using it. The reliability of data is important as
well.
Conversational class applications are the most delay sensitive, whereas background classes are the least
delay sensitive. In general, interactive and background classes require higher reliability. This can be
achieved by providing higher channel coding and retransmissions.
QoS Classes and HSPA (continued)
2-22
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
QoSQoS Classes and HSPA Classes and HSPA (continued)(continued)
- Background download of emails
- Destination is not expecting the data within a certain time
- Preserve payload content
BackgroundBest Effort
- Web browsing
- Request response pattern
- Preserve payload content
Interactive Class
Best Effort
- Streaming video
- Voice, video callExample of the application
- Preserve time relation (variation) between information entities of the stream
- Preserve time relation between entities of stream
- Conversational pattern (stringent and low delay)
FundamentalCharacteristics
Streaming Class
Real Time
Conversational Class
Real Time
TrafficClass
Initial HSPA usage
2-23
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
At this point, the Node B and the Serving Radio Network Controller (SRNC) are working together to
allow packet access to the mobile. An Asynchronous Transfer Mode (ATM) ATM Adaptation Layer type
2 (AAL2) bearer is set up for the user plane. This is done using the Node B Application Part (NBAP)
protocol between the Controlling Radio Network Controller (CRNC) functionality of the Radio Network
Controller (RNC) (within the same RNC in this example) and the Node B.
Key parameters of the Radio Link Setup message:
• Uplink scrambling code
• Channelization codes (UL & DL)
• Transport format set, protection choice
• Everything needed for the NodeB to talk to and hear the UE
The SRNC now turns its attention toward the mobile to set up the various layers in the mobile for the
packet session. This is done using the RRC protocol using the existing control plane that was set up
earlier.
Radio Link Setup
2-24
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
PS-CN PDNIub Iu
Physical Channel
UserPlane
Radio Link SetupRadio Link Setup
RNCNode BControlPlane
Uu
IuRRC
NodeB ready to talk/listen to UE
Protocol: NBAPConfigure ASIC to communicate with UESetup Transport Format Set
AAL2 Bearer
Radio Link Setup Request
Radio Link Setup Response
Bearer Synch AAL2 Bearer allocated
RAB Assignment Request
2-25
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
An example of the Call Admission Control process is shown in the table, which provides an example of
the Radio Network Controller (RNC) configuration for all services by a service provider.
As seen in the table, the Serving Radio Network Controller (SRNC) chooses to allow or disallow the
call based on several reasons. Using the specified criteria, the SRNC then decides to ask the Node B if it
can create the necessary radio links required to complete this session. This is done by issuing a Node B
Application Part (NBAP) Radio Link Setup message to the Node B, which contains the request to use
HSDPA channels for this data session and the QoS requirements of this data session.
The Node B receives this message, handles the request and provides feedback to the SRNC about this
session. This feedback might allow the call or to reject the call due to congestion in the cell (too many
UEs allocated to the HS-DSCH, not enough bandwidth for a high speed HS-DSCH, too much
interference, etc.).
Call Admission Control (CAC)
2-26
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
Call Admission Control (CAC)Call Admission Control (CAC)
SRNC
Node B
RAB Complete
Radio Link Setup (NBAP)
Radio Link Setup Response (NBAP)
Radio Bearer Setup (RRC)
Radio Bearer Setup Response (RRC)
Inform Mobile
Call Admission Control
RAB Assignment (QoS)
PacketSwitched
Core Network
Consult Node B
UE
2-27
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
Once the radio link between the SRNC and the Node B has been set up, the physical channel between the
mobile and the Node B is set up. To this end, a Radio Bearer Setup message is sent.
The path of this RRC message is the same as in the voice call scenario:
DCCH (logical channel) → DCH (transport channel) → DPCH over the air
The peer RRC layer in the mobile receives this message and starts processing the information.
Key parameters of the Radio Bearer Setup message include:
• RLC parameters (PDU size, mode: Acknowledge, Transparent or Unacknowledged)
• Convolution Encoder (transport channel configuration)
• Spreading factor/channelization code (physical channel configuration)
• Transport Format Set and Transport Format Combinations
• RRC Transaction Identifier that will be used for all communications and the RRC state that the
mobile needs to be in (CELL_DCH)
• Information on Packet Data Convergence Protocol (PDCP) for the mobile.
The mobile is completely configured to provide packet data transfer using this RRC message. The
response to this message indicates if the mobile is ready for this data transfer and proceeds with other
signaling required to complete the packet data transfer.
Radio Bearer Setup
2-28
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
PS-CN PDNIub Iu
UserPlane
Radio Bearer SetupRadio Bearer Setup
RNCNode BControlPlane
Uu
IuRRC
RB – setup packet traffic path
Protocol: RRCPhysical Layer setup
AAL2 Bearer
Radio Bearer Setup
Radio Bearer Setup CompleteUE in
Cell_DCHstate
Physical ChannelPhysical Channel
2-29
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
Here is an example of how the packets coming from the core network (CN) are received by the Serving
Radio Network Controller (SRNC) and then passed down the appropriate layers.
The PDCP (Packet Data Convergence Protocol) layer principally is involved in two areas:
1. Convergence between the radio layers and the network layers for ease of transition to other
protocols or technologies in the future
2. Provides a compression mechanism negotiated with the mobile as per Internet RFC2507
The Radio Link Control (RLC) provides a reliability mechanism that is employed here for packet session
since this is NOT a delay-constrained application. This was indicated in the Quality of Service (QoS)
request that was sent up by the mobile and agreed to by the network. The acknowledged mode of the RLC
is chosen to enhance reliability.
The Medium Access Control (MAC) provides a mechanism to resolve contention and allow information
with different priorities to flow through. It also provides a mechanism to map logical channels denoted by
Dedicated Traffic Channel (DTCH) (in this figure) to a Dedicated Channel (Transport channel). It requests
information from the appropriate RLC queues and passes them on to the physical layer (which is present at
the Node B).
The Physical layer is present at the Node B and is responsible for all physical layer functions. The
transport channels received in the Node B are processed and sent over the air.
All working parameters are set up so these layers can work together and with the RRC.
RRC Configures its Layers for Downlink
2-30
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
PDCP
RLC
MAC
DTCH
DCH
SRNC
RRC Configures its Layers for DownlinkRRC Configures its Layers for Downlink
Traffic from Packet Core
Network
RRC state cell_DCH
RAB ID=Radio Bearer ID
Acknowledged Mode
Allowed Formats and
Protection Characteristics
DPCH
Phy
Compression algorithm based on
RFC2507
2-31
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
The Serving Radio Network Controller (SRNC) has two roles:
1. Create the required radio-related configurations. This has been accomplished so far with the
creation of appropriate layers in the mobile and SRNC.
2. Create the necessary associations between the core and radio network. A General Packet Radio
Service (GPRS) Tunneling Protocol (GTP) User Plane tunnel is created and this association is
used to carry packet traffic between the SRNC and core network (CN). This enables packet
transfer to be reliably handled through a private IP backbone.
Since the appropriate tunnels and traffic paths have been created, the process of creating of all the
components of a Radio Access Bearer (RAB) are completed. This results in a Radio Access Bearer (RAB)
assignment complete message, as shown, to the CN. The CN then proceeds with any completion of
signaling that is required to continue with the packet session establishment.
It is also possible that the UTRAN is not capable of handling the request or is in the process of working on
the request from the CN. For such cases, provisions exist in the standard to send a RAB assignment
response that indicates the status or outcome of the request.
Completing the RAB
2-32
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
PS-CN PDNIub Iu
UserPlane
Completing the RABCompleting the RAB
RNCNode BControlPlane
Uu
RAB Assignment Request
IuRRC
UTRAN is ready!
GTP-U
AAL2 BearerPhysical Channel
Radio Bearer (RB)
RAB Assignment Response
RAB = RB + Iu (GTP) Bearer
Create the GTP-U tunnel
2-33
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
At this point, all bearer channels are set up for carrying traffic. In response to the Packet Data Protocol
(PDP) Context Request from the user equipment (UE), the core network (CN) sends a PDP Context
Accept, which indicates to the mobile that the CN has provided the mobile with resources needed for
packet transfer.
The CN also provides the negotiated QoS which may or may not be the same as the requested QoS from
the mobile. The mobile may also have requested an IP address, and this is indicated in this message as
well. All the ingredients for web surfing have been completed at this point.
Surf on, Sue!
Session Setup Completion
2-34
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
Session Setup CompletionSession Setup Completion
RNCNode B
PS-CN PDN
ControlPlane
Iub IuUu
Iu
Let’s start surfin’!
RRC
RAB = RB + Iu (GTP) Bearer UserPlane
DT (Activate PDP Context Accept)
UE may be assigned IP address, informed of
negotiated QoS
2-35
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Summary
2-36
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
SummarySummary• Call setup and packet session setup share
common messaging for the UTRAN• Packet session setup is more complex than
voice calls due to variations in the QoS• The MAC layer performs multiplexing and
resource coordination• The RLC layer coordinates reliability and
performs ciphering
2-37
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Review Questions
2-38
Mastering HSDPA/HSUPA Signaling
UMTS Basic Data Call Setup
Review QuestionsReview Questions1. What are the key differences between a
call setup and a packet session setup?2. What are the key parameters
communicated to the RNC in the RAB Assignment Request?
3. What is the purpose of the RLC layer?4. What are the differences in the physical
channel requirements between a packet session and a call?
2-39
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
HSPAHSPA Key ConceptsKey Concepts
3-1
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Objectives
3-2
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
ObjectivesObjectivesAfter completing this module, you will be able to:
• Describe the fundamental difference between uplink and downlink
• Contrast the link adaptation philosophies of UMTS R99, HSDPA and HSUPA
• Describe in simple terms the meaning and principles of Hybrid ARQ and Incremental Redundancy
• Sketch at a high level the steps involved in the operations of HSUPA and HSDPA
• Contrast the allocation of resources between the two HSPA technologies
3-3
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
There are fundamental diffeences between the uplink and downlink in CDMA-based systems. In the
downlink, orthogonal channelization codes are used to separate different channels within a cell. This
prevents one user’s data in a cell from interfering with another user’s data. The downside is that only a
limited number of codes can be allocated in a cell. Between two cells, a scrambling code is used to
separate information. Since these codes are not orthogonal, the information of one cell does interfere with
the information on another cell. Because of this interference, the transmitted power needs to be minimized
to limit the interference.
In the uplink, scrambling codes are used to separate one UE’s transmission from another. Hence,
information one user transmits interferes with data transmission from all nearby users. In addition, a
number of individual UEs transmit data on the uplink simultaneously. To maintain the uplink interference
levels within base station design limit, we need to design a better uplink resource allocation algorithm that
manages all the UE transmissions. Uplink does not suffer from code space limitations like the downlink.
The base station seprates the received signals using the scrambling code first and as a result all UEs in a
cell may use the same code set without constraints.
Uplink vs. Downlink
3-4
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
Uplink vs. DownlinkUplink vs. Downlink
Node B
UE power limitation, interference control,no code limitation
Code limitation, orthogonal codes, and
centralized power mgmt
3-5
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
This chart compares the different adaptation techniques between an R99 Dedicated Channel, an R5
HSDPA channel, and an R6 Enhanced Dedicated Channel.
For the R99 dedicated channel, two key mechanisms are used to adapt the link. The first mechanism
includes the inner-loop and outer-loop power control algorithms and the ability to set the channel bit rate
via a variable spreading factor. Power control is only used to maintain an acceptable channel quality at a
minimum power level. The channel bit rate is not really a form of link adaptation, but a form of setting the
channel bit rate based on the needed bandwidth of the user’s service.
For the HSDPA channels, the key form of link adaptation is adapting the modulation scheme based on the
channel conditions. In addition, not shown in this chart is the ability to use Hybrid ARQ to minimize the
amount of protection information transmitted over the air.
With HSUPA channels (i.e., the E-DCH), power control and channel bit rate adaptation are used as in
R99. One key difference is that the channel bit rate can be varied by the UE independent of the RNC
based on the channel conditions and the amount of data that is needed. Also, added to HSUPA is the
requirement on the UE to help manage the UL interference based on feedback from the network.
HSDPA and HSUPA both use dynamic scheduling to achieve higher spectral efficiency and throughput
while adapting to current channel conditions.
Link Adaptation Techniques
3-6
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
Link Adaptation TechniquesLink Adaptation Techniques
Power control Channel bit rate (Variable Spreading
Factor)
ONR99
R5 HSDPA
R6 HSUPA
ON
OFF OFF
ONON
Dynamic Scheduling
OFF
ON
ON
Variables
Adaptive Modulation
OFF
ON
OFF
3-7
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
The figure depicts the conceptual operation of Hybrid ARQ.
The user bits are turbo-coded and properly interleaved and repeated to form a coded symbol sequence.
This coded symbol sequence is separated into 3 streams of data which are called the systematic, parity1
and parity 2 bits.
Next, the transmitter selects some of these symbols to be transmitted to the receiver. In the first
transmission, the HARQ process prioritizes the systematic bits. Typically, the first transmission has a 90%
chance of success. This portion is sent to the receiver. The receiver decodes these symbols and tries to
determine the original user bits by matching them with a possible physical layer CRC value. In this
example, we show that the receiver has not been able to decode the user bits completely and sends a
negative acknowledgement (NACK) to the transmitter.
After receiving a NACK, the transmitter again sends some more symbols from the coded symbol sequence
– parity 1. The receiver now combines symbols of both systematic and parity bits and decodes them to
figure out the original user bits.
This process continues until the receiver successfully decodes the symbols and sends an acknowledgement
(ACK), or until the transmitter decides to stop sending the coded symbols, whereby the upper layers (i.e.,
RLC or TCP) try to recover from the errors.
Hybrid ARQ Operation
3-8
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
Hybrid ARQ OperationHybrid ARQ Operation
Receiver
Coded Symbol Sequence
NACK ACK
Transmitter
Systematic bits Parity1 Parity2
Systematic bits Parity1
Parity1Systematic bits
Systematic bitsReceiver Buffer
Parity1
Decoded Symbol Sequence
No need to send P2
3-9
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
Let’s discuss how the HSDPA High Speed Downlink Shared Channel (HS-DSCH) operates at a 10,000
foot level. Multiple UEs may be assigned to the HS-DSCH by the RNC since it is a shared channel. HS-
DSCH operations may be summarized in the following 4-step procedure:
1. The first step in the HS-DSCH operation sequence is the Carrier-to-Interference (C/I) reporting by
all the UEs assigned to the HS-DSCH. Each mobile on the HS-DSCH measures its radio
conditions and provides the Node B with an accurate idea of the current receiving condition. The
Node B gathers the C/I report from all the UEs before proceeding to the next step. The UEs may
report the C/I value once every 2 milliseconds.
2. The scheduler is executed at the Node B to determine which user’s data should be transmitted
next. The standards do not specify the scheduling algorithm. Hence, the scheduling algorithm and
the assignment approach differ from one implementation to another.
3. The data is transmitted to the selected user. When the scheduler selects a user, it uses the C/I value
reported by the UE and the data buffer waiting for transmission to determine the data rate and
modulation scheme for the transmission. The Node B uses the selected configuration to send the
data over-the-air.
4. The UE receives the data and verifies the checksum. If the transmission was received properly, the
UE (who received the data) transmits an ACK to the Node B. If the transmitted information was
received with errors, the UE sends a NACK to the Node B.
These steps are repeated continuously to support the HS-DSCH effectively.
HSDPA Process Overview
3-10
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
HSDPA Process OverviewHSDPA Process Overview
High-Speed Data Transmission
Node B
ACK/NAK
12
3
4
SchedulerSupporting Control Information
Run the Scheduling Algorithm
Channel Quality1
1
UE 1
UE 2
UE 3
Channel Quality
Channel Quality
UE 1
UE 1
---- 10101010101
3-11
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
In HSDPA, the RAN can use a portion of downlink capacity as a shared channel in Time Division
Multiplexed (TDM) or Code Division Multiplexed (CDM) mode.
The serving Node B continuously receives the radio condition reports (CQIs) from all the UEs that are
requesting a higher data rate in the downlink. The Node B collects this information, and, based on several
other factors such as availability of user data, QoS, available transmit power, etc., schedules the downlink
transmission of packets to all the UEs over the shared channel. Short scheduling time units are used to
reduce inefficiencies and waste of the radio resources.
In TDM, a resource is utilized by different entities (e.g., UEs) at different times. In an HSDPA system, the
high speed channel transmits data in 2 ms intervals. When this channel utilizes TDM, only one user is
given data during a TTI. In the example shown here, the 2 ms TTI is given to User 3 first. No data is
transmitted on the high speed channel to any other user during this TTI. In the third 2 ms TTI, User 2 is
given data using the high speed channel. In the fifth 2 ms TTI, User 1 is given data on the high speed
channel. A different number of OVSF codes (at SF= 16) can be assigned to different users at different
times. The advantage of the TDM approach is simple implementation, but the disadvantage is that other
users need to wait to receive data on the high speed channel. For this reason, HSDPA also supports the
Code Division Multiplexing mode of operation. In CDM, a resource is utilized by different entities (e.g.,
UEs) at exactly the same time. When this channel utilizes CDM, multiple users receive data during a given
TTI. In the example shown here, in the second 2 ms TTI, User 1 and User 2 simultaneously receive data.
In the fourth 2 ms TTI, User 3 and User 2 are given data using the high speed channel. A different number
of OVSF codes (at SF= 16) can be assigned to different users during the same TTI, as well as during
different TTIs. The advantage of the combined TDM and CDM approach is more flexibility serving users
since the users requiring short latency (or delay) do not need to wait as long as they would if only TDM
were available. The disadvantage of the combined TDM-CDM approach is the complexity of
implementation. Note that HSDPA transmission in the downlink is completely asynchronous (i.e., the
packets sent on each TTI can be assigned to a UE at any time so that all the active UEs must be constantly
listening to the signaled scheduling information to find out whether a transmission is directed to them).
Asynchronous Transmission in HSDPA using CDM/TDM
3-12
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
Asynchronous Transmission in Asynchronous Transmission in HSDPA using CDM/TDMHSDPA using CDM/TDM
Node B
UE1
UE2
UE3
CQI
CQI
CQI
Downlink Transmission
UE3. . .UE2
UE2 UE1UE2
UE1UE3
3-13
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
A Node B is configured for certain transmit power (i.e., 20 to 40 watts). Some portion of this power is
allocated to control or overhead channels such as the Pilot, Forward Access Channel (FACH), and Paging
Channel (PCH). The remaining power is dynamically allocated to all the active users for their forward
traffic channels. Here the users at the edge of the sector, due to inferior channel conditions or to combat
other interference sources, need higher power to compensate for path loss. Similarly, the users near the
center of the sector are allocated much less power to their forward traffic channels. Since voice traffic
needs roughly a constant data rate, link adaptation is achieved through the change in transmit power. This
is called “fixed rate variable power” where the sector varies the transmit power but maintains a fixed
throughput to the user no matter where the user is located.
As depicted in the figure, the available transmit power is not utilized maximally at all times in a UMTS
R99 system. Since HSDPA systems are designed to support both voice and higher data rate packet data
users simultaneously, they need to support the downlink power management philosophy from UMTS R99
as well as add an efficient way to use the remaining power to provide high speed data. For voice and
medium rate data users, HSDPA systems maintain the traffic frame rate and adjust the transmit power by
performing fast downlink power control. This allows the HSDPA system to serve multiple voice users
with a symmetric low data rate bandwidth requirement.
However, for high-speed data users, the HSDPA system adopts the philosophy of allocating the remaining
available transmit power to a single user at any given time and adjusting the data rate based on the channel
conditions observed by the data user.
In other words, for voice and medium rate data users, the HSDPA system adjusts its transmit power, and
for higher rate data users, it adjusts its downlink data rate to accommodate varied radio conditions
observed by the users throughout the cell.
Power Management in HSDPA
3-14
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
Power Management in HSDPAPower Management in HSDPA
TransmitPower
Time
MaxTDM/CDM Packet
Data ChannelU1 U2 U3U4
Overhead Channels
Voice and R99 data usersDOWNLINK
2ms
Available Pwr
Unused power in R99can be used for HSDPA
• Only ONE Node B transmits High Speed Channel
• Power assigned from a single CELL only
3-15
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
In a UMTS R99 system, the downlink channels are identified by a unique Spreading Factor (SF) code on
the Orthogonal Variable Spreading Factor tree (OVSF). The SF codes vary in length from 4 bits to 512
bits. The SF codes are generated as shown. Out of these SF codes, certain codes are reserved for control
channels such as the pilot channel or the channel that broadcasts the system information broadcast for the
cell. The total number of OVSF codes at a given SF is the same as the SF. For example, there are 8
orthogonal codes at SF = 8. The HSDPA system uses the fixed SF of 16. There are 16 OVSF codes at SF
= 16. A maximum of 15 OVSF codes at SF = 16 can be used for HSDPA. These 15 codes can be assigned
to a single user during a TTI, or they can be shared among multiple users during the TTI. The voice users
and the HSDPA users share the same OVSF code tree.
Since HSDPA supports both voice and higher rate packet data users, spreading factor code management
becomes very critical. SFs for voice users are typically 128 bits in length. However, for high rate data
users, the length of the spreading factor codes can be quite short (up to 4 bits) for Dedicated Physical
Channels (DPCH) in UMTS R99 systems.
Thus, the co-existence of voice users and packet data users, both based on DPCH and HSDPA packet data
channels, poses important challenges for spreading factor code management.
OVSF Code Tree for HSDPA
3-16
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
OVSF Code Tree for HSDPAOVSF Code Tree for HSDPA
C 1,0 = (1)
C 2,0 = (1, 1)
C 2,1 = (1,-1)
C 4,0 = (1, 1, 1, 1)
C 4,1 = (1, 1,-1,-1)
C 4,2 = (1,-1, 1,-1)
C 4,3 = (1,-1,-1, 1)
SF = 1
C 8,0
C 8,1
C 8,2
C 8,3
C 8,4
C 8,5
C 8,6
C 8,7
SF = 2 SF = 4 SF = 8
15 codes with SF=16 are available for HSDPA
…SF =16
C 16,0
HSDPA
SF = 32
3-17
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
HSDPA systems achieve higher data rates for packet data services by introducing a number of
optimizations over the air. These optimizations are:
Fat-pipe scheduling: HSDPA systems use fat-pipe scheduling to achieve higher data rates. Time Division
Multiplexing (TDM) on new packet data channels is introduced in HSDPA. The entire set of packet data
channels is allocated to a single user for a specific duration. This allows the system to support 14 Mbps
services to users.
Dynamic channel estimation: The HSDPA system is based on the “variable power variable rate”
principle. The mobile station estimates and reports the channel quality for every scheduling period.
Higher order and adaptive modulation: HSDPA systems use higher order modulation techniques such
as Quadrature Phase Shift Keying (QPSK) and 16QAM (Quadrature Amplitude Modulation). The higher
order modulation schemes enable the system to push more bits through the air. The selection of
modulation is dynamic. That is, in every scheduling period, one of the modulation schemes is used based
on the existing radio conditions. The support for QPSK is mandatory, while the support for 16QAM is
optional.
Early acknowledgement schemes: Early acknowledgement is one of the Hybrid Automatic Repeat
reQuest (HARQ) schemes. The network schedules packet transmission to the system every scheduling
period. If the packet is successfully transmitted before the scheduled period is over, the remaining time
may be used for the next packet. Thus, the spectrum utilization is quite efficient.
Effective use of residual power: In HSDPA, power for transmission of high-speed channels in the
downlink is normally taken from the remaining power in the base station. This method of power allocation
in the cell makes effective use of power resources and avoids any intervention with power resources
allocated to other channels (like voice channels). However, the use of remaining power in the base station
limits the possibility of doing efficient power control in the downlink.
High Data Rate – Top Contributors
3-18
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
High Data Rate High Data Rate –– Top ContributorsTop Contributors
Adaptive and Higher Order Modulation
Dynamic Channel Estimation
& Fast Feedback
Early Acknowledgement and Incremental
RedundancyChannel-sensitive
& Fat PipeScheduling
Effective Use of Residual Power in
the Downlink
IncreasedSpectral Efficiency
& Throughput
3-19
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
HSUPA systems achieve higher data rates for packet data services by introducing a number of
optimizations over the air. These optimizations are:
Flexible bandwidth scheduling: HSUPA systems use a flexible bandwidth scheduling scheme to achieve
higher data rates. In the uplink, the UE’s transmit power varies based on the current channel conditions,
QoS requirements, and the amount of data that needs to be transmitted.
Dynamic & fast scheduling: The HSUPA system is based on the “variable power variable rate” principle.
The base station understands the needs of the UE and the current uplink interference level, and sends an
allocation of allowed uplink radio resources for the UE to use.
Early acknowledgement schemes: As with HSDPA, HSUPA utilizes the early acknowledgement scheme
of the Hybrid Automatic Repeat reQuest (HARQ). The UE schedules packet transmission to the system
every scheduling period. If the packet is successfully transmitted before the scheduled period is over, the
rest of the time may be used for the next packet. Thus, spectrum utilization is quite efficient.
Effective management of uplink interference: In HSUPA, power for transmission of high-speed
channels in the uplink is normally taken from available remaining power. This method of power allocation
in the cell makes effective use of power resources and avoids any intervention with power resources
allocated to other channels (like voice channels). The use of remaining power in the cell, however, limits
the possibility of performing efficient power control in the uplink.
High Data Rate – Top Contributors
3-20
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
High Data Rate High Data Rate –– Top ContributorsTop Contributors
Dynamic schedule requests
& Fast scheduling
Early Acknowledgement and Incremental
Redundancy
Channel-sensitive & Flexible BandwidthScheduling
Effective Management of
Uplink Interference
IncreasedSpectral Efficiency
& Throughput
3-21
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
The HSUPA process can be described in five basic steps. Note that the duration of time between the first
and last step is in the order of 10 ms.
1. The UE makes a scheduling request.
2. The scheduling requests of all of the UEs are received by the serving Node B. These requests
become important inputs to the scheduler algorithm in the Node B. The scheduler’s main task is
to determine the amount of power to allocate to each UE. The standards do not specify the
scheduling algorithm. Hence, the scheduling algorithm and the assignment approach differ from
one implementation to another.
3. Resources are granted to the selected users. When the scheduler selects a set of users, it uses the
uplink channel quality and the data bandwidth requests from the UE to decide the resource
allocation. The Node B signals the resource allowances over the air to the UEs.
4. The UE sends the data to the Node B which verifies the checksum.
5. If the transmission was received properly, the Node B (who received the data) transmits an ACK
to the UE. If the transmitted information was received with errors, the Node B sends a NACK to
the Node B.
These steps are repeated continuously to support the high-speed process effectively.
The HSUPA Process Overview
3-22
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
The HSUPA Process OverviewThe HSUPA Process Overview
Serving Node B
Scheduling Request1
Scheduler
Run the Scheduling Algorithm
3 Granting allowed resources
High Speed Data+Associated signaling
4
ACK/NACK5
Node B
Node B
2
3-23
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
When a UE transmits, it adds to the total interference in the uplink. As a result, an acceptable threshold
limit needs to be set. This limit is called the Rise over Thermal Threshold. It represents the amount of
interference that can be added to the uplink frequency above the thermal noise before the interference
becomes too high to decode any uplink information.
All of the UEs currently transmitting information on channels in other cells contribute to this interference.
Other sources of interference include, the UEs transmitting on dedicated channels in the cell in question
and the sum of the users that are transmitting on the E-DCH channels. As was have seen in HSDPA, the
goal is to share the available power that remains after allocating dedicated channels for high-speed packet
data (in this case it is for uplink high-speed packet data.).
The uplink interference management designed for HSUPA is used to manage the available power
efficiently to maximize the amount of data that can be transmitted in the uplink without sacrificing the
channel quality for the users that have been assigned dedicated channels (i.e., the voice calls).
UL Power/Interference Management
3-24
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
UL Power/Interference ManagementUL Power/Interference Management
Thermal Noise
UEs on other cells
UE 1
UE 2UE n
Noise due to E-DCH channels
RoT Threshold
Each UE adds to the noise level. The noise level must be managed so that it stays below a threshold
Node B
3-25
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
In a UMTS R99 system, the downlink channels are identified by a unique Spreading Factor (SF) code on
the Orthogonal Variable Spreading Factor tree (OVSF). The SF codes vary in length from 4 bits to 512
bits. The SF codes are generated as shown. Out of these SF codes, certain codes are reserved for control
channels such as the common pilot, and primary and secondary common control channels.
Since HSUPA supports a range of rates for packet data users, SF code selection is critical in determining
the achievable data rate. HSUPA uses a spreading factor of length 2 bits on the uplink to achieve high data
rates. When lower data rates are required, HSUPA uses higher length spreading codes. The peak rate of
5.76 Mbps in HSUPA requires he use of a 2-bit and a 4-bit spreading factor. The lowest data rate in
HSUPA is 15 kbps, and the corresponding spreading factor is 256 bits long.
OVSF Code Tree for HSUPA
3-26
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
OVSF Code Tree for HSUPAOVSF Code Tree for HSUPA
C 1,0 = (1)
C 2,0 = (1, 1)
C 2,1 = (1,-1)
C 4,0 = (1, 1, 1, 1)
C 4,1 = (1, 1,-1,-1)
C 4,2 = (1,-1, 1,-1)
C 4,3 = (1,-1,-1, 1)
SF = 1
C 8,0
C 8,1
C 8,2
C 8,3
C 8,4
C 8,5
C 8,6
C 8,7
SF = 2 SF = 4 SF = 8
…
SF = 16 SF = 256…
These codes are used for max data rates in HSUPA
3-27
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
Hybrid ARQ is defined for the downlink in R5 (HSDPA) and for the uplink in R6 (HSUPA). While they
have a lot of similarities in how they function, there is a key difference. In R5 HSDPA, HARQ is strictly
asynchronus. In other words, there is no fixed time relationship between two successive subpacket
transmissions. The HSDPA scheduler decides when a certain subpacket may be sent, and the scheduler
has full discretion to decide how many subpackets it will transmit for a given packet.
In R6, HSUPA is defined with strict timing relationship between subpackets of a given packet. This is
done to help with UE implementation. Each MAC flow is defined at radio bearer setup time with a
maximum number of HARQ retransmissions. The physical layer definition in the standards define a strict
timing relationship between two subpackets. For a 2 ms TTI, two subpacket transmission start times are
exactly 16 ms apart. For a 10 ms TTI, the inter subpacket start interval is defined as 40 ms. Unless a
positive ACK obviates the need for a subsequent subpacket, the next subpacket is sent using the
previously mentioned timing relationship.
Synchronous HARQ in UL
3-28
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
Synchronous HARQ in ULSynchronous HARQ in UL
P2
SP2
P1
SP2
P2
SP1
P1
SP1
Fixed
Fixed
• Asynchronus in HSDPA & strictly synchronous in HSUPA• Inter subpacket interval is defined as:
- 2 ms TTI: 16ms- 10 ms TTI: 40ms
3-29
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Summary
3-30
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
SummarySummary• HSDPA and HSUPA use different link
adaptation techniques• HSDPA uses a fixed SF and adaptive
modulation• HSUPA uses variable SF and fixed modulation• Both technologies rely on a fast scheduling
mechanism• HSDPA operation is asynchronous on the
network side • HSUPA operation is fully synchronous
3-31
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Review Questions
3-32
Mastering HSDPA/HSUPA Signaling
HSPA Key Concepts
Review QuestionsReview Questions1. Compare link adaptation in R99, R5 and
R6.2. Explain major differences between the UL
and DL.3. How does HARQ operate?4. Give a summary of HSDPA operations?5. How are OVSF codes used in HSPA?6. Why does HSDPA operate asynchronously
while HSUPA operation is synchronous?
3-33
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSDPA HSDPA Data Call SetupData Call Setup
4-1
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Objectives
4-2
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
ObjectivesObjectivesAfter completing this module, you will be able to:
• List the RRC and radio bearer setup enhancements
• List the channel assigned during the HSDPA call• Describe how the UE selects the CQI during an
HSDPA data call• List the various types of radio reconfigurations
used during HSDPA data call set up• Describe the operation of the various types of
handover in HSDPA
4-3
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The support of the HSDPA feature requires enhancement in RRC, MAC and physical layer protocols.
Some of the major RRC enhancement procedures required are mentioned below. The requirements vary
between R5 and R6 implementation.
1. RRC connection establishment needs enhancement to support HSDPA capabilities on the UE side
and assignment of signaling radio bearers for the control plane.
2. A new transport channel and both UL and DL channels have been introduced for HSDPA support.
The RRC has to be enhanced to assign these new channels for both uplink (control) and downlink
(control and user data).
3. Radio bearer setup and reconfiguration have been enhanced to configure logical channels, HS-
DSCH transport channels and physical channels according to QoS requested by the core network.
4. HSDPA employs Adaptive Modulation and Coding (AMC) techniques to support high speed
downlink data. To provide the best possible QoS to the user, the UTRAN requires feedback from
the UE about the downlink radio conditions. The UE periodically sends Channel Quality Indicator
(CQI) reports on the UL to the Node B. The Node B uses this as one of the parameters to schedule
the downlink data in the next TTI (Transmission timing interval ) for that UE. There are 31 CQI
values for each UE category.
5. The RRC decides, coordinates and executes handovers during an HSDPA call. This can be within
sectors of the serving Node B or Inter Node B/Inter RNC.
The MAC layer is also enhanced to support downlink data scheduling and handling of priority data based
on QoS. The MAC-d has been enhanced to support different MAC-d flows from different logical channels
and their priority. The MAC-hs has been introduced in HSDPA for scheduling downlink data and it is
located at the Node B. Based on CQI reports sent by the UE, QoS requested, and UE categories, the
MAC-hs executes an algorithm to schedule downlink data, which can be sent every 2 ms TTI.
HSDPA Enhancements
4-4
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSDPA EnhancementsHSDPA Enhancements
RRC Enhancements
CQI selectionHARQ + IR
Handover Procedures
(Best cell change)
DL SchedulingPower management
UE-RRCRNC-RRC
Node B
MAC-hs/Modulation RL Setup changes
Radio Bearer Enhancements
4-5
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The figure depicts an overview of the procedures involved in the data call setup scenario. The first
mandatory procedure is to set up resources for the control plane. Therefore, the scenario starts with the
RRC Connection Establishment to create the UE-UTRAN signaling connection. Once the RRC
connection has been established, the UE contacts the Core Network (CN) using the first NAS message
(here called Service Request). As usual, the CN may or may not initiate the security procedures like
Authentication. Assuming that the outcome has been successful, the UE starts the login procedure, which
also is a request for an IP address. This procedure is called PDP Context Activation, which also involves
the negotiation of the QoS parameters.
After a successful negotiation, the SGSN triggers the setup of resources for the user plane using the RAB
Assignment procedure. Here, we assume that, based on the QoS parameters, the RNC always sets the cell
DCH to be the RRC state for the UE to establish the HSDPA radio bearer. Therefore, it starts the Radio
Link Setup procedure toward the Node B on the Iub interface. Once the RNC and the Node B have further
synchronized the bearer, the RNC can start the Radio Bearer Setup procedure over the air interface. The
PDP context procedure is finalized with an Accept message sent by the SGSN to the UE.
HSDPA Data Call Setup
4-6
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSDPA Data Call SetupHSDPA Data Call SetupUE RNC GGSN
1. RRC Connection Establishment
2. Service Request
3. Security Procedures
4. PDP Context Activation Request
6. RL Setup 5. RAB Assignment
7. Radio Bearer Setup
Node B SGSN
Bearer Synch
8. PDP Context Accept
4-7
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The first step to start the HSDPA data call scenario is the creation of resources for the control plane.
Between the UE and UTRAN this is done according to the RRC Connection Establishment. RRC
connection establishment is enhanced in R5 to support HSDPA functionality. RRC connection
establishment involves 3 steps:
1. RRC Connection Request sent by the UE (Reference specs 25.331):
This message is sent on the RACH Transport channel. The UE sends its
• Initial Identity: PTMSI, TMSI and Routing area Identity (RAI)
• Establishment Cause: Originating streaming call, originating interactive call, originating
background call, etc.
• Support of access stratum of higher releases than REL 99, in this case R5
• No HSDPA-related parameters are sent in this message in R5
2. RRC Connection Setup sent by the UTRAN (Reference specs 25.331)
This message is sent by the RNC to the UE on the FACH transport channel. The UTRAN sends
the following to the UE:
• Various Signaling Radio Bearer (SRB) information to be set up - mapping of logical
transport and physical channels
• The UE ID and UTRAN –RNTI (U-RNTI)
• The RRC indicator for the UE (e.g., Cell DCH)
• UE Capability Requirement: If set to “True”, then the UE has to send its Radio access
capabilities when it responds to this message
• No HSDPA-capable parameters are sent in this message
RRC Connection Enhancement - R5
4-8
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
RRC Connection Enhancement RRC Connection Enhancement -- R5R5UE RNC
1. RRC Connection Request
2. RRC Connection Setup
• Capability update required?
3. RRC Connection Complete
• HS-DSCH Physical layer category
No HSDPA Related Parameters
4-9
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
3. RRC Connection Complete (Reference specs 25.331)
The UE now enters the Cell DCH state and sends the last RRC message, RRC Connection Setup
Complete, for the establishment of the RRC Connection. It sends the CN domain ID and, if asked
in the RRC Connection Setup, its Radio Access Capability. This message is sent using the RLC-
AM, and the RNC responds with an RLC Status PDU (an acknowledgement) to handshake the
start of the acknowledge mode with the UE. The UE sends the radio access capability, which
contains:
• Downlink capability with simultaneous configuration (32,64,128,384 kbps)
• Physical channel capability, which indicates the support for the HS-PDSCH and physical
layer category (UE categories 1-12). Each UE category indicates the maximum number of
HS-DSCH codes it can receive (minimum inter–TTI interval, maximum number of bits a
HS-DSCH transport block can receive within an HS-DSCH TTI and total number of soft
channel bits). The Node B uses this as one of the key inputs to its scheduling algorithm.
RRC Connection Enhancement - R5 (continued)
4-10
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
RRC Connection Enhancement RRC Connection Enhancement -- R5 R5 (continued)(continued)UE RNC
1. RRC Connection Request
2. RRC Connection Setup
• Capability update required?
3. RRC Connection Complete
• HS-DSCH Physical layer category
No HSDPA Related Parameters
4-11
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The Service Request is defined as the Initial Direct Transfer message in UMTS. It is sent to the RNC by
the UE containing the UE identity in the PS domain (P-TMSI), a reference number to the latest
authentication procedure (Key Set Information (KSI)) and the type of service (Signaling).
On receiving the Initial Direct Transfer (Service Request) from the UE, the RNC further transfers the
request to the SGSN using a Connection Oriented message to set up the Iu connection.
The SGSN in response starts authentication and security procedures. This includes the security mode
command, which includes the specified ciphering and integrity protection algorithm to be used by the
UTRAN along with the keys used for the same. Once the security procedures are completed, all
subsequent signaling and the data is sent securely over the air interface.
When all the bearer channels are setup for carrying traffic, the UE sends the SM Activate PDP Context
Request for SGSN. This is carried by the RRC Direct Transfer message, which is sent over the Iu interface
by the RANAP protocol. The message describes the service that the UE wants to activate and contains the
requested QoS profile. The message includes an NSAPI, which is added to identify this PDP context. To
communicate with the PS Domain, it is essential to have information regarding the IP address. It also
includes the requested PDP address parameter and Access Point Name (APN), which determines the entity
that allocates the IP address. The message also includes the Logical Link Control Service Access Point
Identifier (LLC- SAPI).
The SGSN now receives the Activate PDP Context message from the RNC using the RANAP DT over Iu
connection. Once it receives the request, it first uses the APN to find the GGSN, and then starts a
“handshake’ with the GGSN to negotiate the QoS parameters and create the GTP tunnel.
In response, the GGSN sends a Create PDP CTX Request to the RNC, indicating that the core network has
provided the mobile with resources needed for packet transfer. The message also includes the negotiated
QoS profile with the UE IP address. Since we are going to create a GTP tunnel, the tunnel endpoint
identity (TEIDS) and GGSN IP address are also sent.
When compared to R99, no changes are required in the service request to support HSDPA. The only
difference is that a higher QoS can be supported.
Service Request
4-12
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Service RequestService RequestUE RNC GGSNInit. Dir. Transfer (Service Req.)
CR[IUM (Service Req.)]
UL DT (Activate PDP CTX Req.)
DT (Act. PDP CTX Req.)
SGSN
Create PDP CTX Req.
Security Procedures
Create PDP CTX Resp.
Check subscription: APN & QoS
Use APN GGSN addr
No changes for HSDPA except that higher QoS canbe negotiated
4-13
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
When the service between GGSN and SGSN is negotiated with a specific Quality of Service (QoS)
profile, the SGSN sends a RANAP RAB Assignment Request message to the RNC to set up user plane
resources.
The RAB Assignment is the mechanism for the CN to notify the UTRAN of the appropriate QoS and
attributes required to deliver the service. This request is translated into a Radio Link Setup Request sent
from the Radio Network Controller (RNC) to the Node B via Node B Application Part (NBAP) signaling,
and eventually a Radio Bearer Setup message sent from the RNC to the User Equipment (UE) via Radio
Resource Control (RRC) signaling. Once the radio resources have been assigned and set up, the RAB
Assignment Response completes the RAB by setting up the Iu (GTP) between the SGSN and RNC in the
case of a packet-switched data call, this is an ATM Adaptation Layer Type 5 (AAL5) connection.
Radio Access Bearer Assignment
4-14
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
UserPlane
Radio Access Bearer AssignmentRadio Access Bearer Assignment
RNCNode B
PS-CN PSTN
ControlPlane
Iub IuUu
IuRRC
Setup Radio Link
AAL2 BearerPhysical Channel
Setup Radio Bearer
Iu/AAL5
Complete the RAB
Radio Bearer (RB)
UE
RAB RB+Iu (GTP) bearer defines required QoS
4-15
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
When the RAB Assignment Request is sent by the Core Network (CN) to the RNC, which includes the
RAB ID and QoS that will indicate a need for relatively high bit rates in downlink. Some additional
inquiry regarding UE capability is required in R5/6 to support HSDPA.
If the UE Capability was not received during the RRC Connection Complete message, the UTRAN asks
for the mobile capability using the UE Capability Inquiry message. The most interesting information
element here, for the RNC, is the so-called “UE Category”.
Since the RNC has requested a capability update, the UE sends the UE Capability Information. The most
valuable piece of information here is whether the UE supports HSDPA and, if so, its category. These
parameters are included in the DL Capability with Simultaneous HS-DSCH Configuration and the
Physical Channel Capability.
UE Capability
4-16
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
UE CapabilityUE Capability
Node B
UE
RNC
UE Capability Inquiry
CN
RAB Assignmt Req.
UE Capability Information
Only if not sent in RRC
Connection Establishment
4-17
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The figure describes the architecture of the MAC and functional split required to support HS-DSCH on the
UTRAN side. As shown in the example, the logical channels are based on QoS, and associated with user
data. This diagram shows 4 logical channels: DTCH1,DTCH 2,DTCH 3 and DCCH. These Logical
channels are multiplexed to produce MAC-d PDUs.
• C/T MUX: The function includes the C/T field when multiplexing several dedicated logical
channels onto one MAC-d flow.
• MAC –d Flow: It is a flow of MAC –d PDUs belonging to logical channels that are MAC-d
multiplexed. These MAC-d PDUs that have multiplexed data from several logical channels that
are called MAC-d flows.
In our example, DTCH 1 and DTCH 2 are multiplexed to produce one MAC-d flow named MAC-d flow
1, and DTCH 3 and DCCH are multiplexed to produce MAC-d flow 2.
The RNC then sends the configuration parameters to the Node B on the Radio Link Setup Request over
the Iub interface using the Node B Application Part (NBAP) protocol which includes the following:
• Associated MAC-d Flows with MAC-d Flow ID: Each MAC-d flow is identified by a MAC-d
flow identifier on the QoS and application.
• Priority queue identifier: Each MAC-d flow can have several priority queues, which are
identified by the priority queue ID.
UTRAN MAC
4-18
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
UTRAN MAC UTRAN MAC
MAC-d Flow: 1
RNCNode B
MAC-hs
RL Setup Request
PriorityQueue
PriorityQueue
PriorityQueue
PriorityQueue
Priority queue distribution
HARQ ENTITY
TFRC Selection
HS-DSCH
DTCH 1 DTCH 2 DCCHDTCH 3
C/T MUX
MAC-d flow: 1 MAC-d Flow: 2
ConfigureConfigure• Associated MAC-d flows with identifiers• Priority queue identifiers
MAC- d
C/T MUX
4-19
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The MAC-hs layer has the following functional blocks:
• Priority Queue Distribution: This function manages HS-DSCH resources between HARQ
entities and data flows according to their priority class. It sets the priority class identifier and
Transmission Sequence Number (TSN) for each new data block being serviced. The TSN is sent
on the MAC-hs header to the UE by the Node B.
• Priority Queue: The MAC-hs, based on priority of flows, stores this data in priority queues which
are designated with the unique queue identifier.
• HARQ: One HARQ entity handles the hybrid ARQ functionality for one user and is capable of
supporting multiple instances (HARQ process) of stop and wait HARQ protocols. There is one
HARQ process per TTI.
• TFRC Selection: It performs the selection of an appropriate transport format and resource
combination for the data to be transmitted on the HS-DSCH.
UTRAN MAC (continued)
4-20
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
UTRAN MAC UTRAN MAC (continued)(continued)
MAC-d Flow: 1
RNCNode B
MAC-hs
RL Setup Request
PriorityQueue
PriorityQueue
PriorityQueue
PriorityQueue
Priority queue distribution
HARQ ENTITY
TFRC Selection
HS-DSCH
DTCH 1 DTCH 2 DCCHDTCH 3
C/T MUX
MAC-d flow: 1 MAC-d Flow: 2
ConfigureConfigure• Associated MAC-d flows with identifiers• Priority queue identifiers
MAC- d
C/T MUX
4-21
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The figure illustrates the architecture of the MAC on the UE side.
The UE receives the data and performs physical layer functions, such as demodulation, based on
Modulation type, descrambling, and despreading of OVSF codes.
• HARQ: The HARQ functional entity is responsible for handling all tasks required for Hybrid
ARQ and for generating ACKs or NACKs.
• Reordering Queue Distribution: Its function is to route the MAC-hs PDUs to the correct re-
ordering buffer based on the Queue ID. The re-ordering buffer reorders received MAC-hs PDUs
according to the received TSN. The TSN and Queue ID are part of the MAC-hs headers
• Dis-assembler :The dis-assembler is responsible for the disassembly of MAC-hs PDUs. When a
MAC-hs PDU is disassembled, the MAC-hs header is removed, and the MAC-d PDUs are
delivered to a higher layer.
• MAC –d Flow: It is a flow of MAC–d PDUs that belong to logical channels which are MAC-d
multiplexed. These MAC-d PDUs, which have multiplexed data from several logical channels,
are called MAC-d flows.
• C/T MUX: It is used to de-multiplex a MAC-d flow into several logical channels.
In our example, MAC- d flow 1 is de-multiplexed into the corresponding logical channels DTCH1 and
DTCH2. MAC-d flow 2 is de-multiplexed into the corresponding logical channels DTCH3 and DCCH.
The RNC configures the UE with logical channel identifiers, associated MAC-d flows and priority queue
identifiers in the Radio Bearer Setup message.
UE MAC
4-22
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
UE MACUE MAC
• Associated MAC-d flows with identifiers• Priority Queue identifiers• Logical channel IDs• HARQ Processes
DCCHDTCH 1 DTCH 2 DTCH 3
MAC-d
Flow: 1 Flow: 2
MAC-hs
C/T MUXC/T MUX
RNC
RRC RRCRadio Bearer Setup
Configure
MAC-d
UE
MAC-d
4-23
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The High Speed Shared Control Channel (HS-SCCH) is the control channel associated with the HS-
DSCH. The HS-SCCH transmits the HS-DSCH channel allocation information including the user
identification, codes allocated and the modulation scheme of the current burst. Since the HS-SCCH is
associated with the HS-DSCH, it exists only on the downlink. The HS-SCCH transmits HS-DSCH
allocation information 1.3 ms before the HS-DSCH burst is transmitted. In other words, the HS-DSCH
content-related control information is transmitted over the air slightly ahead of the HS-DSCH data
transmission, giving the UE enough time to “receive” the HS-DSCH burst correctly.
It is important to note that the HS-SCCH does not carry any upper layer signaling information. The HS-
SCCH carries only the control information for the HS-DSCH, which is sometimes known as MAC control
information.
Unlike the HS-DSCH, the HS-SCCH uses the fixed modulation scheme of QPSK, with SF = 128.
The HS-SCCH can be power-controlled by the Node B. There is no downlink soft handover for the HS-
SCCH.
Typically, the HS-SCCH and the HS-DSCH channels are used in pairs. The HS-SCCH carries the control
information of the HS-DSCH, and the HS-DSCH carries the user traffic. So, in a typical deployment, we
may have one HS-DSCH and one HS-SCCH in a cell. However, multiple HS-SCCHs can be supported in
a cell. The UE can monitor up to four HS-SCCH channels.
HS-SCCH assignment can be carried by the following:
• An RRC Connection Setup message in R6 during configuration of the signaling radio bearer
• An RL Setup Response sent by the Node B to the RNC in response to an RL Setup Request sent
by the RNC
• Once the Node B sends an RL Setup Response to the RNC, the RNC sends an RRC Radio Bearer
Setup message to the UE
HS-SCCH Assignment
4-24
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--SCCH AssignmentSCCH Assignment
UE RNCNode B
RRC Connection Setup (R6)
Radio Bearer Setup(R5 & R6)
HS-SCCH info
DL SC-DefSC of CPICH
RL Setup Response (R5 & R6)
SF = 128
Can Configure 1 to Max HS-SCCH Codes
per Cell
Up to 4 per UE
4-25
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
All 3 messages carry:
• One to four HS-SCCH codes: This can be configured in the UTRAN to indicate how many HS-
SCCH codes can be used in this cell.
• For each HS-SCCH configured, the above-mentioned messages indicates the channelization code
of the HS-SCCH. The spreading factor for the HS-SCCH is always 128.
All UEs assigned to the HS-DSCH have to monitor the HS-SCCH(s) before receiving data on HS-
PDSCH(s).
HS-SCCH Assignment (continued)
4-26
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--SCCH Assignment SCCH Assignment (continued)(continued)
UE RNCNode B
RRC Connection Setup (R6)
Radio Bearer Setup(R5 & R6)
HS-SCCH info
DL SC-DefSC of CPICH
RL Setup Response (R5 & R6)
SF = 128
Can Configure 1 to Max HS-SCCH Codes
per Cell
Up to 4 per UE
4-27
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The Node B fills in parameters in the HS-SCCH on a dynamic basis.
• Channelization Code Set (CCS): This field is the number of spreading factor codes that are used
in this HS-DSCH for a 2 ms frame. The field consists of the location offset of the set of codes (4
bits) and number of OVSF codes (3 bits). The UE reads this Information on the HS-SCCH and
decodes the actual channelization codes which are used in the downlink.
• Modulation Scheme (MS): The data can be sent using either QPSK or 16QAM. This field
communicates which modulation scheme is used.
• Transport Block Size (TBS): In UMTS R99, all data that is sent to the UE is broken down into a
transport block. The field communicates the size of this transport block. The TBS is 6 bits and this
does not directly send actual transport block size. The HS-SCCH carries only the index that is 6
bits long, from which the UE can determine the actual size of the transport block.
• Hybrid ARQ Parameters (HAP): This parameter (HARQ Process Identifier) identifies the
HARQ process (or buffer) where the data is placed. A maximum of 8 processes can be handled by
the HARQ entity at the UE. Every 2 ms, the scheduler sends the packet corresponding to that
HARQ process. So, the HARQ process identifier can indicate to the UE which HARQ process the
current packet belongs to so the UE can process and assemble the information.
• Redundancy and Constellation Version (RV): Since we use turbo encoding in HSDPA, the
output consists of three streams of redundant data. The RV parameter implies the percentage of
real user data and what percentage is redundant data in the current transport block. It is planned as
a per scheduling algorithm whether the first packet is just the real transport block with no
redundant data or subsequent blocks can be the redundant data to help fix the error received in the
original “original data” transport block.
HS-SCCH Contents
4-28
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--SCCH ContentsSCCH Contents
NDI CRCRVHAPTBSMSCCS
7 1 6 3 3 1 16
4-29
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Each retransmission may use a different redundancy version, where each redundancy version is a different
subset of the coded bits. Each subset may contain a different number of bits. Chase-combining
corresponds to defining or using only a single redundancy version.
The redundancy version (RV) parameters r, s and constellation version parameter b are coded jointly to
produce the value Xrv. This is done according to the tables mentioned in the Standard according to the
modulation mode used.
• QPSK: RV Parameters (s, r)
• 16-QAM: RV Parameters (s, r, b)
• s: “1” to prioritize systematic bits; “0”, otherwise
• r: Choice of the set of parity bits
• b: Signal constellation rearrangement for 16-QAM.
• New Data Indicator (NDI): This field indicates whether this packet is the beginning of a new
transport block or part of an existing transport block
• CRC: After all of the above data is determined, a 16 bit CRC check is calculated.
1. This CRC is then masked with the H-RNTI of the subscriber that this packet is intended
for.
2. The UE receives the HS-SCCH information, performs a CRC calculation, and applies its
H-RNTI to the CRC.
3. If the CRC matched the received CRC, the data is for it; otherwise the UE disregards this
packet.
HS-SCCH Contents (continued)
4-30
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--SCCH Contents SCCH Contents (continued)(continued)
NDI CRCRVHAPTBSMSCCS
7 1 6 3 3 1 16
4-31
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Before a mobile can receive information on the HS-PDSCH(s), the UE must be assigned, via a Radio
Bearer Setup message, the necessary HS-SCCH information. The UE is also communicated the H-RNTI
that will be used to inform the UE when data is being sent to it.
In this example, UE1 has been assigned H-RNTI 1, and UE2 has been assigned H-RNTI 2.
All UEs store their H-RNTI, and they de-spread the HS-SCCH(s) using the information sent in the Radio
Bearer Setup message, for example CC = 6 and SF = 128.
HS-PDSCH Assignment
4-32
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--PDSCH Assignment PDSCH Assignment
UE1 (H-RNTI 1)
UE2 (H-RNTI 2)
Radio Bearer SetupH-RNTI 1, Max HS-SCCH=1, CC=6, SF=128
H-RNTI 2, Max HS-SCCH=1, CC=6, SF=128
ALL UEs store their H-RNTIAll UEs de-spread HS-SCCH with CC=6,
SF=128
Radio Bearer Setup
Node B
4-33
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Now, the HS-SCCH control data is sent on a particular 2ms TTI interval. Both UEs first de-spread the HS-
SCCH and look into the control data, which denotes the necessary information for monitoring and
processing of their scheduled user data in the subsequent 2ms TTI interval. The steps involved in this
process of decoding control data sent on HS-SCCH include:
1. Both UE1 and UE2 unmask the CRC sent on the HS-SCCH. This example indicates that the
CRC is masked with H-RNTI1.
Result: UE1 understands that this control information is meant for it and will receive the HS-
PDSCH data in the subsequent 2 ms TTI interval.
2. UE1 decodes the CCS, which is offset = 2, and the number of OVSF codes = 2.
Result: UE1 finds that it has been assigned 2 codes, which are CC = 1, SF = 16 and CC = 2, SF =
16.
3. UE1 now decodes the transport block size, which denotes TFRI = 1.
Result: The UE decodes and identifies that its assigned TBS is 1239 bits.
4. UE1 determines the modulation type, which can be QPSK or 16QAM. This example denotes that
the modulation type bit is set to 1.
Result: UE1 understands that this is16QAM.
5. UE1 identifies the RV value, which is denoted here as s = 1, r = 1, and b = 0.
Result: UE1 identifies that chase combining is used with constellation rearrangement.
HS-PDSCH Assignment
4-34
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--PDSCH Assignment PDSCH Assignment
1TBS index
1,0,0RV (s, r, b)
1M
0010001CCS
H-RNTI1UE ID masked with CRC
UE1 (H-RNTI 1)
UE2 (H-RNTI 2)
HS-SCCH contents(2 ms TTI)
UE 1 side
UE 1/ UE2 unmask its CRC with its H-RNTI It is H-RNTI 1 (UE 1)
UE1 decodes CCS001=code group ind0001=code offset ind
No of OVSF codes=2, offset=2
CC 1, 16 and CC 2, 16
Determines the size of Transport blockTBS value =1
TBS Value =1 corresponds to 1239 bits
Determines Modulation type and RVModulation=16QAM and RV value uses chase combining
with constellation rearrangement
Node B
4-35
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The High Speed – Dedicated Physical Control Channel (HS-DPCCH) is the channel used by a UE to
report current information about the link and the status of incoming packets. The current receiving radio
conditions are reported with the Channel Quality Indicators (CQI). The status of the incoming packet is
communicated with a Hybrid ARQ ACK (HARQ ACK).
On the uplink, each UE sends the quality report and CQI on its HS-DPCCH every 2 ms while it is
assigned an HS-DSCH. Since the HS-DPCCH is used to determine the possible rate of transmission to a
UE on the HS-DSCH, the HS-DPCCH does not exist and is not used when a UE is not on the HS-DSCH.
Please note that the mobile sends CQIs all the time as long as the HS-DSCH is assigned to it. It does not
matter whether the Node B is scheduling the UE’s user traffic on the HS-DSCH.
A UE uses the HARQ ACK on the HS-DPCCH to send an acknowledgement (ACK) or negative
acknowledgement (NACK) to the Node B. The ACK corresponds to a successful packet reception and the
NACK corresponds to an unsuccessful packet reception on the HS-DSCH. The UE decodes the received
packet at the physical layer. If the packet is received successfully, the mobile sends these ACK/NAK
responses back to the base station. Since this occurs at the physical layer, this mechanism is very fast and
achieves increased throughput.
Since the HS-DPCCH is associated with an HS-DSCH, each mobile on the HS-DSCH has one HS-
DPCCH. The Node B configures the UE to send the ACK/NACK at a fixed offset from the end of a
subpacket reception. Since the HARQ ACK transmission is related to a subpacket reception, the mobile
station does not transmit the HARQ ACK when it does not receive a subpacket on a HS-DSCH.
The UE derives HS-DPCCH channelization codes implicitly from the maximum number of DPDCHs (
NMAX DPDCH) signaled on the message.
• RRC connection setup (Only R6)
• Radio link setup response, NBAP message from the Node B to RNC (once the RNC receives this
message, it forwards this parameter to the UE in the Radio Bearer Setup message.
HS-DPCCH Assignment
4-36
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--DPCCH DPCCH AssignmentAssignment
SPREADINGHS-DPCCH
SPREADING
∑
ScramblingCode
HS-DPCCH
(If NMAX DPDCH=0, 1, 3, 5)
Chs
Chs
(If NMAX DPDCH =2, 4, 6)
4-37
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The NMAX DPDCH can take values from 0 to 6. Each value indicates the possible combinations of
channels in the uplink. These channels can have different combinations of DPDCH, HS-DPCCH and E-
DPDCH/E-DPCCH (R6 ). The possible combinations are documented in 25.213 specifications.
Based on NMAX DPDCH values, the UE knows the corresponding channelization codes of the HS-
DPCCH. The spreading factor for the HS-DPCCH is always 256.
NMAX DPDCH =0 corresponds to HS-DPCCH channelization code C ch,256,33
NMAX DPDCH =1 corresponds to HS-DPCCH channelization code Cch,256,64
NMAX DPDCH = 2,4,6 corresponds to HS-DPCCH channelization code Cch,256,1
NMAX DPDCH = 3,5 corresponds to HS-DPCCH channelization code Cch,256,32
HS-DPCCH Assignment (continued)
4-38
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--DPCCH DPCCH AssignmentAssignment (continued)(continued)
SPREADINGHS-DPCCH
SPREADING
∑
ScramblingCode
HS-DPCCH
(If NMAX DPDCH=0, 1, 3, 5)
Chs
Chs
(If NMAX DPDCH =2, 4, 6)
4-39
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
There ate two components of the HS-DPCCH to support the downlink high-speed operation:
HARQ-ACK/NACK and CQI are channel-coded and then mapped to the physical channel. The HARQ-
ACK /NACK is transmitted in the first slot and the CQI is transmitted in the next two slots.
The HARQ-ACK/NACK is processed in parallel and sent at different times on the HS-DPCCH.
The structure of the HARQ-ACK/NACK and CQI are given below:
• HARQ = ACK/NAK:
Input: 1 bit
Output: 10 bits after Channel coding
ACK: All 1s
NACK: All 0s
• CQI
Coding scheme (20,5)
Input: 5 bits
Output: 20 bits after channel coding
The CQI can take values between 0 (no data) and 30 (maximum data rate)
Structure of HS-DPCCH
4-40
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
StructureStructure of of HSHS--DPCCHDPCCH
# of O/P bits
CQI
Channel
Coding
HARQ
10 bits 20 bits
ACK: All 1sNACK: All 0s
HARQ(ACK,NACK)
CQI(0 to 30)
# of I/P bits
Channel
Coding
(20, 5)
20 bits
HS-DPCCH
C 256, hs
PhysicalChannelMapping
10 bits
4-41
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The UE transmits the CQI on the HS-DPCCH to the Node B. If the Node B transmits data using the CQI
parameters, the DL BLER is 10% or less under current channel conditions. For every UE category, a table
is defined in the standard that associates a CQI value with a set of parameters. The CQI includes the
following parameters:
TFRC Info: The TFRC is based on the resources currently being employed by the Node B for the UE,
and refers to the possible transport formats and modulation schemes as configured by higher layers. It also
includes the number of HS-PDSCHs.
• The UE assumes HS-PDSCH power by taking into account PHSPDSCH = PCPICH + Γ +∆. The UE uses
this assumption to determine whether, for the current radio conditions, it is able to receive data with
a transport format corresponding to a BLER of approximately 10%.
• TFRC reporting is more robust than C/I reporting since there may be inequality between receivers
at the UE. The receivers may perform differently for the same observed channel conditions.
Reference Power Adjustment ∆: It is also called the power reduction factor. This factor introduces a 1
dB difference in the assumed power for the best channel conditions when the maximum transport block
size can be received.
Measurement Power offset Γ: The measurement power offset Γ is sent in the Radio Bearer Setup
message. It indicates a positive or negative offset applied on CPICH power ( -6…… 13, in .5 dB steps).
This is used to bias the CPICH power so the UE can receive higher or lower HS-PDSCH power. This
causes the UE to report a higher or lower transport format block size, keeping the target BLER < .1. As a
result, the Node B can schedule data more or less based on the buffer queue to be transmitted in 2 ms TTI.
CQI Fundamentals
4-42
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
CQI FundamentalsCQI Fundamentals
TFRC info
Ref PowerAdjustment
MeasurementPower Offset
CQI ReportingCycle
CQI RepetitionFactor
• TB size• Modulation Type• No of HS-PDSCHs
• Power ReductionDL QualityExceeds UE Capability
HS-PDSCH Power= CPICH+ Offset Γ
• CQI Reporting Period≥ 2 ms
• No. of times CQI reported
PHSPDSCH = PCPICH + +∆Γ is sent in the Radio Bearer Setup message∆ is the Reference power adjustment which UE refers from CQI Table
Γ
CQI
4-43
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
CQI Reporting cycle: This parameter, also called CQI feedback cycle K, indicates the frequency of
transmission of CQI reports by the UE on the HS-DPCCH. K can assume values from 0, 2, 4, 8, 10, 20,
40, 80, and 160 in units of ms. For K = 0, the UE does not transmit the CQI value. The UE reports a CQI
value over the next consecutive HS-DPCCH subframes on slots allocated for the CQI. A low feedback
cycle is intended for some or all UEs having relatively less activity, static channel conditions, or low
capability, or if the Node B has high traffic load.
CQI Repetition factor: Based on CQI Reporting cycle K, this parameter determines the number of times
the CQI report is transmitted. It can assume values ranging from 1 to 4.
CQI Fundamentals (continued)
4-44
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
CQI Fundamentals CQI Fundamentals (continued)(continued)
TFRC info
Ref PowerAdjustment
MeasurementPower Offset
CQI ReportingCycle
CQI RepetitionFactor
• TB size• Modulation Type• No of HS-PDSCHs
• Power ReductionDL QualityExceeds UE Capability
HS-PDSCH Power= CPICH+ Offset Γ
• CQI Reporting Period≥ 2 ms
• No. of times CQI reported
PHSPDSCH = PCPICH + +∆Γ is sent in the Radio Bearer Setup message∆ is the Reference power adjustment which UE refers from CQI Table
Γ
CQI
4-45
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
This diagram shows an example of parameters that influence CQI repetition.
The CQI feedback or reporting cycle and CQI repetition factor are the two parameters that take care of
CQI repetition. The UE transmits the ACK/NACK information received from the MAC-hs in the slot
allocated to the HARQ ACK in the corresponding HS-DPCCH subframe as defined approximately 5 ms
after HS-DSCH subframe reception.
The UE follows a feedback cycle of 4 ms. This means every 4 ms the UE transmits a CQI value. Since the
CQI repetition factor is set to 2, a new report is only sent after two CQI transmissions.
The diagram illustrates the fact that CQI reporting and ACK/NACK reporting do not necessarily occur
within the same subframe.
If the UE does not have to be served within every subframe, the CQI reporting cycle can be set to a longer
value.
CQI Repetition
4-46
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
CQI RepetitionCQI Repetition
Frame No. 0 Frame No. 1 Frame No. 2 Frame No. 3
# 0
# 1
# 2
# 3
# 5
# 4
# 6
# 7
# 8
# 9
# 10
# 11
# 12
# 13
# 14
# 15
# 16
# 17
# 18
# 19
HS-DPCCH Subframes
HS-DSCH
#2
HS-DSCH
#5
HS-DSCH
#6
HS-DSCH
#7
HS-DSCH
#8
HS-DSCH
#3
HS-DSCH
#9
HS-DSCH#11
HS-DSCH#13
HS-DSCH#12
HS-DSCH#18
HS-DSCH#16
HS-DSCH#14
HS-DSCH#15
HS-DSCH#19
HS-DSCH#17
HS-DSCH#20
5 ms
5 ms
5 ms
CQI #2
CQI #2
HS-DSCH
#1
HS-DSCH
#4
HS-DSCH#10
AN
AN
CQI #1
AN
CQI #1
AN
CQI Feedback Cycle K= 4 msCQI Repetition Factor =2
4-47
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
CQI parameters are signaled to the UE and Node B by the RNC when it receives the RAB Assignment
Request from the SGSN with a specified QoS.
The RNC signals the Node B on the RL Set Request message, which is a NBAP message with the
following:
• CQI feedback cycle, K
• CQI repetition factor N_CQI transmit
• Measurement Power offset Γ
• N_ACK-NACK transmit. This indicates the number of times ( NACK/NACK transmit) the
ACK/NACK can be retransmitted on its specified slots on HS-DPCCH subframes.
• CQI power offset ∆CQI. This indicates the power offset of HS-DPCCH relative to DPCCH power
when the CQI is transmitted.
• ACK/NACK Power offset ∆ACK/NACK. This indicates the power offset of the HS-DPCCH relative
to DPCCH power when the ACK/NACK is transmitted on specified slots of HS-DPCCH
subframes.
• UE Physical layer category
On receipt of this message, the MAC-hs at the Node B configures these parameters and responds with an
NBAP RL Setup Response message.
The RNC then forwards all of the above parameters in the Radio Bearer Setup message to the UE.
When HS-DSCH data transmission starts, the UE monitors the data and reports the CQI value based on
current radio conditions. It uses the above parameters to report, retransmit the CQI periodically, and also
apply power offset to the HS-DPCCH when the CQI and ACK/NACK are transmitted.
CQI Measurement Feedback Signaling
4-48
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
CQI Measurement Feedback SignalingCQI Measurement Feedback SignalingUE Node B SGSN
RL Setup RequestRNC
RAB Assignment Request
RL Setup Response
Radio Bearer Setup
Radio Bearer Setup Complete
4-49
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The estimation and reporting of the CQI by the UE helps the MAC-hs scheduler at the Node B determine
the TFRC information. The CQI report is one of the inputs to the Node B scheduler to determine the
transport block size format, number of HS-PDSCH channelization codes, modulation type based on
previous CQI reports, and current DL quality, which can be used in the next HS-DSCH data transmission.
It also guarantees a BLER of approximately 10%.
The UE determines the CQI value by measuring the Ec/No of the pilot, and for purposes of reporting
applies the formula given below:
PHSPDSCH = PCPICH + Γ +∆
Γ is sent in the Radio Bearer Setup message.
∆ is the Reference Power Adjustment in the CQI mapping table
The total received power is equally distributed among the different channelization codes of the reported
CQI value.
Besides using the power of HS PDSCH, it checks the varying parameters such as TB size, modulation
type, number of HS-PDSCH codes and reference power adjustment to provide a CQI value. The result of
this process is transport block size, modulation type, etc,. which maintains a BLER ≤ 10%. This is an
iterative algorithm that keeps running until a BLER of ≤ 10% is achieved.
The UE reports one of the CQI values 0 to 30. A lower CQI value indicates poorer channel conditions.
Each CQI value ranging from 0 to 30 has a different transport block size, modulation type, number of HS-
PDSCH channelization codes and reference power adjustment. All of these parameters vary for different
UE categories.
CQI Reporting
4-50
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
CQI ReportingCQI Reporting
BLER ≤ 10%
TB size
Modulation Type
No. of Spreading Codes
P(HS-PDSCH)
Reference power adjustment ∆
UE Categories (1-12)
CQI value0-300 – out of rangesignaling
HS- DPCCH
CQI Values sent to Node B
CPICH (Ec/No)
4-51
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
UE Category : There are 12 UE Categories. The mapping of CQI values, TB size, modulation type,
reference power adjustment, maximum number of HS-PDSCH codes, incremental redundancy buffer size
(NIR) and redundancy version values (Xrv) for each UE category are provided in specification 25.214.
Transport Block Size (TBS): The TBS for each UE category and CQI value indicates the maximum
transport channel bits it can receive in a 2 ms TTI.
Spreading Codes: For each UE category, this indicates how many maximum HS-PDSCH spreading
codes the UE can receive in a 2 ms TTI. The range is from 1 to 15.
Modulation Type: UE categories 1 to 10 can support both QPSK and 16QAM, whereas categories 11 and
12 support only QPSK.
Reference Power Adjustment ∆: The ∆ is specified for each UE category and CQI value in the CQI
mapping table. The ∆ can take a value equal to 0 or negative values. Negative values indicate that the UE
is able to receive the highest transport format according to its category with less HSPDSCH power. It also
means that channel conditions have improved in the downlink as reported by UE, so that the Node B in the
next TTI can send the highest transport format according to the UE category but with less power compared
to the previous HS-DSCH data transmission.
NIR and Xrv: The NIR indicates the total number of soft channel bits present in the Virtual IR buffer per
HARQ process. The Xrv denotes the redundancy version depending on the UE category. UE category 10
has the maximum soft channel bits.
CQI Reporting (continued)
4-52
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
CQI Reporting CQI Reporting (continued)(continued)
BLER ≤ 10%
TB size
Modulation Type
No. of Spreading Codes
P(HS-PDSCH)
Reference power adjustment ∆
UE Categories (1-12)
CQI value0-300 – out of rangesignaling
HS- DPCCH
CQI Values sent to Node B
CPICH (Ec/No)
4-53
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
This slide shows an example of the usage of different reference power adjustment values and the resulting
impact on HS-PDSCH DL power. The category used is 1.
1. The UE reports a CQI value of 17 on the UL HS-DPCCH. CQI = 17 corresponds to the MAX
TBS = 4189 bits, the number of OVSF codes = 5, modulation =16QAM, ∆ = 0, NIR = 9600 bits,
and Xrv =0.
2. The scheduler at the Node B uses this CQI value and other parameters to determine the TBS,
OVSF codes, and modulation type and sends the information on the HS-SCCH to the UE. Then, it
runs the algorithm and decides to send TBS = 4189 bit, the number of OVSF codes = 5,
modulation = 16QAM, RV = 0, and HAP = 1 on the HS-SCCH.
3. The UE monitors the HS-SCCH and decodes the HS-SCCH information. Now it receives HS-
DSCH data on the next 2ms TTI.
4. The UE now uses the formula to assume HS-PDSCH power and probes the TBS size, OVSF
codes, modulation type, etc. to check whether the BLER is ≤ 10%. In this case, it determines that
the BLER is approximately 8%. Please note that the mapping of -13 dB to 8% BLER is just an
example. The actual mapping of parameters to BLER is vendor implementation-specific.
5. Now it sends CQI = 23, which is a higher value. This indicates that channel conditions are good,
so that the UE can receive a maximum of 7168 transport block bits, with ∆ = -1. This is an
indication to the Node B that the UE can still receive a maximum of 7168 bits with lesser HS-
PDSCH power.
Reference Power Adjustment - Example
4-54
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Reference Power Adjustment Reference Power Adjustment -- ExampleExample
High-Speed Data Transmission (HS-DSCH)
Node B
Channel Quality (HS-DPCCH)
2
3
4
SchedulerSupporting Control Information (HS-SCCH)
Run the Scheduling Algorithm
Channel Quality (HS-DPCCH)1
UE (Category 1) CQI=17, ACK
TBS=4189 bits, #OVSF codes=5Modulation=16QAM, ∆=0, NIR =9600bits,
Xrv =0
TBS=17 (4189 bits), #OVSF codes =5, Modulation=16QAM, RV=0, HAP=1
P HSPDSCH=P CPICH+Γ +∆=-13db+0+0
-13db ~ 8% BLER
5
CQI=23, ACK
TBS=7168 bits, #OVSF codes=5Modulation=16QAM, ∆=-1, NIR=9600 bits
Xrv=0
4-55
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Up to this point, the RNC has been informed by the SGSN about the requested QoS parameters, and has
also found out exactly what the UE may be able to support. Therefore, it is now time to start preparing the
Node B for the traffic. For that reason, the RNC sends the Radio Link Setup over the Iub interface using
the Node B Application Part (NBAP) protocol. This message contains all the parameters it had for R99,
but it now has the HSDPA-related parameters as well. Some important parameters include:
1. Associated MAC-d flows, MAC-d flow ID and Priority queue ID
2. UE Physical layer Category: There are 12 UE categories. The RRC already has the information
about the UE category that was previously sent on the RRC Connection Setup Complete or UE
capability information. This provides the Node B with useful information for scheduling downlink
data like the maximum number of channelization codes supported by the UE, maximum transport
blocks supported per TTI, etc.
3. CQI and ACK/NACK Parameters: Channel quality indicator parameters and ACK/NACK
parameters related to HARQ processes are sent. HARQ types such as chase combining and
incremental redundancy are supported by the Node B. The UE sends an ACK/NACK for every
transmission on the uplink along with the CQI on the HS-DPCCH channel.
4. H-RNTI: A new HS-DSCH-RNTI can be sent to manage the mobility of the UE during the
HSDPA transaction.
RL Setup Enhancements – R5 & R6
4-56
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
RL Setup Enhancements RL Setup Enhancements –– R5 & R6 R5 & R6 UE Node B SGSN
RL Setup Request
RNC
RAB Assignment Request
RL Setup Response
4-57
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Upon reception of the RL Setup Request message, the Node B answers with the Radio Link Setup
Response. Again, on top of all Release 99-related parameters, we also see the HSDPA-related parameters,
such as:
1. Binding ID and Transport Layer Address: For every MAC-d flow, the Node B configures the
Binding ID and transport layer address. The binding ID binds the AAL2 adaptation for the Iub.
2. HS-SCCH Information: The Node B also sends the RNC the maximum number of HS-SCCH
codes supported in this cell and the channelization code of supported HS-SCCHs.
3. HARQ Processes: Based on MAC-d flows and priority queues, the MAC-hs scheduler in the
Node B creates the maximum number of HARQ processes. Each 2 ms TTI supports only one
HARQ process, and the UE can receive several HARQ processes during its reception. The MAC-
hs partitions the soft buffer memory (soft channel bits) equally among the HARQ processes. The
maximum number of soft channel bits are fixed for each UE category.
4. Initial capacity allocation: The MAC-hs also indicates the maximum MAC-d PDU size and
scheduling priority indicator for each priority queue. The maximum number of priority queues the
MAC-hs can handle is also sent in this message.
RL Setup Enhancements – R5 & R6 (continued)
4-58
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
RL Setup Enhancements RL Setup Enhancements –– R5 & R6 R5 & R6 (continued)(continued)
UE Node B SGSN
RL Setup Request
RNC
RAB Assignment Request
RL Setup Response
4-59
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
After negotiation and setting up pf the resources on the Iub interface, the RNC sends the Radio Bearer
Setup message to the UE. Here, the UE is assigned a new H-RNTI which is only valid for the HSDPA
operation. In addition to all other Release 99 parameters, the UE also receives information about the
HSDPA channel assignment. Here, the most important ones include information related to the new
channels. In an information element, called DL HS-PDSCH Info, the UE receives the essential parameters
(scrambling and channelization code(s)) to decode the HS-SCCH and maximum number of HS-SCCHs
supported in this cell. It also includes information about how to send the CQI parameters. In addition, the
Γ (measurement power offset) parameter is sent to help the UE calculate the power of the HS-PDSCH.
This RRC message also carries logical channel IDs and their priorities, MAC-d flow IDs, the priority
queue ID, added HS-DSCH transport channel information, and the maximum number of HARQ processes
for the UE to configure them internally. It also carries the serving HS-PDSCH RL (radio Link) indicator.
The UE acknowledges the reception of the Radio Bearer Setup message by sending the Radio Bearer
Setup Complete message. On the Iu interface, using the RANAP protocol, the RNC now sends the RAB
Assignment Response to notify the SGSN that all the resources within the UTRAN have been granted for
the requested QoS.
The SGSN, having made sure that the requirements for the QoS are met, addresses the Activate PDP
Context Accept message to the UE. In this message, the SGSN informs the UE (in addition to all other
mandatory parameters) about the final negotiated set for the QoS.
RAB Setup Enhancements – R5 & R6
4-60
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
RAB Setup Enhancements RAB Setup Enhancements –– R5 & R6R5 & R6UE Node B SGSNRNC
RAB Assignment RequestRadio Bearer Setup
Radio Bearer Setup CompleteRAB Assignment Response
DL DT (Act PDP CTX Accept)
DT (Activate PDP CTX Accept)
4-61
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
What are some of the other factors that affect the scheduling of a high-speed packet data user?
QoS and Subscriber Profile: The Node B may be provided with key information such as a profile of the
subscriber as Gold class, Platinum class, etc. This may provide an indication of the priority associated with
the scheduling of the user.
History: The users’ usage history may be another input into the scheduler. The Node B may maintain
historical information on when the user was scheduled, how long it has been since the user has received
data, etc. The Node B may use this information to prevent “starvation,” where a specific user does not
have to wait an inordinate amount of time before receiving data. This also ensures that the throughput
demands of the user can be maintained.
Traffic Model: Another input may be traffic patterns that are configured in the operator’s network. The
HS-DSCH channel and its usage may vary based on the time of day. It may also vary based on whether it
is off-peak or peak time for data traffic. For example, the operator may want to ensure that voice capacity
is not reduced during peak voice call hours and that other times are available for increased high-speed data
usage. The operator might provide seasonal promotions, which can be another input to the scheduler.
UE capability: The capabilities of the UE also affect the scheduler. For example, the number of
simultaneous Automatic Repeat Request (ARQ) channels that a mobile can support influences the number
of simultaneous channels a Node B uses for a specific mobile. Mobiles may also be limited in the data
rates that they can support, which can factor into the Node B’s scheduler process.
Radio Resource availability: The number of available 16-bit length spreading factor codes can change
periodically depending on the number of UMTS R99 users. A possible approach is to configure the use of
spreading factor codes so that the available number changes only at certain times of the day. The Node B
can use this as another key input to ascertain the schedule of packet data.
The scheduler uses an assortment of static, transient and dynamic information to achieve the optimum
scheduler function. Static information includes the QoS, subscriber profile and traffic pattern
configuration. An example of dynamic information is the feedback received from the UE, such as the CQI
value and ACK/NACK, available spreading factor codes, historical information, etc.
DL Scheduler Inputs
4-62
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
DL Scheduler InputsDL Scheduler Inputs
Scheduled Users & Packet Formation Strategy
Radio ResourcesPower, OVSF Codes
Scheduler
UE CapabilityUser 1: User 2:
Traffic ModelMorning AfternoonEvening Off peak
QoS & Subscriber Profile
User 1: Best effort, silver class
User 2: High priority, platinum
class
HistoryHow long had the user been
waiting?
Feedback from uplink
(CQI, ACK/NACK)
Buffer StatusAmount of Data, Arrival Rate
4-63
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Several scheduling techniques can be implemented at the Node B. The Implementation is manufacturer-
specific. One of the key scheduling techniques, called Proportional Fairness Scheduling, is described here.
We will describe the implementation with an example shown in the diagram.
Let’s consider three users: User 1, User 2 and User 3. These three users are in active packet data state,
which means they are allocated HSDPA Radio Network Temporary Identifiers (H-RNTI) from the
HSDPA network. These three users report CQI values using their individual CQI channels respectively.
The Node B scheduler uses this information to calculate the data rate that can be achieved. We will label
this as the “Data Rate Computed.” This information is updated every 2 ms as the users report their CQI.
R1, R2 and R3 represent the moving averages of the Data Rate Computed values maintained by the
scheduler over a period T for User 1, User 2 and User 3 respectively.
At every scheduling instance, the scheduler has to choose among transmission to three users. The
scheduler transmits to the user with the highest (Data Rate Computed)/R value. The user with the highest
(Data Rate Computed)/R value is considered to be close to its average data rate. If no data is to be sent to a
user, it is not considered in this computation.
Proportional Fairness Scheduling
4-64
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Proportional Fairness Scheduling Proportional Fairness Scheduling
User 3User 1
User 2
CQI 1 CQI 2
CQI 3
User with highest ratio will be scheduled
User 1Data Rate
Computed / R1
R1, R2 & R3 moving average over period T
User 2Data Rate
Computed / R2
User 3Data Rate
Computed / R3
Translate CQI into the data rate for each mobile.
Compute
4-65
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Prior to transmission of scheduled data, the Node B sends HS-SCCH control data. Since the UE knows the
HS-SCCH channelization code, it de-spreads the HS-SCCH and decodes the HS-SCCH contents, which
contain all the required information for UE to receive the HS-PDSCH data.
The output from the scheduler has the following control data:
• H-RNTI: Identification of the user(s) whose data is to be transmitted on the next HS-DSCH sub-
frame
• Transport Block Size: The amount of data to be transmitted for new transmission (same size for
retransmission)
• Schemes for Channel Coding and Redundancy: HARQ process ID, redundancy version and
maximum soft channel bits based on the UE category
• Modulation Type: The type of modulation to be used for the next transmission
• Channelization Code Set: The number of 16-chip OVSF codes to be used for the next
transmission. The scheduled data from the MAC-hs scheduler is multiplexed to the HS-DSCH
transport channel. In each TTI interval, one transport block is transmitted and these channel codes
data are mapped to the HS-PDSCH.
Packet Formation Strategy
4-66
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Packet Packet FormationFormation StrategyStrategy
AdaptiveModulation
(QPSK, 16QAM)
# of OVSF Codes
Selected User(s)
AdaptiveTransport Block Size
(New Transmission)
Adaptive Coding or
Redundancy
Scheduler Outputs info Signaled on HS-SCCH
• H-RNTI
• Transport Block Set (TBS)• New Data Ind (NDI)
• HARQ ProcessIdentifier
• RedundancyVersion (RV)
M - Modulation type
ChannelizationCode Set (CCS)
4-67
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
This slide emphasizes more on MAC-d- and MAC-hs-related functions used to transmit downlink HSDPA
user data.
User data from the SGSN arrives at the RNC. The user data may arrive from an application server in the
form of streaming data, for example. The QoS for this application has already been set up.
The user data passes through the PDCP at the RNC, which may perform compression. After compression,
the user data packets are compressed and sent to the RLC layer. The RLC can act either in AM or UM
mode, which is determined by the higher layer protocols. The RLC can also perform ciphering of the user
packets to maintain integrity and protection when transmitting on the radio interface. The RLC performs
its own functions based on the AM/UM mode. For example, the RLC can do concatenation or
segmentation, and at the same time store each RLC PDU inside a transmission and retransmission buffer.
This helps the RLC retransmit RLC frames in case of RLC frame errors.
The RLC adds its own header information and forwards the RLC PDU to the MAC-d layer at the RNC.
The RLC communicates with the MAC-d through logical channels. There can be several logical channels
based on the QoS associated with user data. In this diagram, there are 4 logical channels: DTCH 1, DTCH
2, DTCH 3 and DCCH. The data from these logical channels can be multiplexed to produce MAC-d
PDUs. These MAC-d PDUs, which have multiplexed data from several logical channels, are called MAC-
d flows.
Several MAC-d flows can co-exist. For example, in this diagram DTCH 1 and DTCH 2 are multiplexed to
produce one MAC-d flow, and DTCH 3 and DCCH are multiplexed to produce another MAC-d flow.
MAC-d can also indicate to the Node B MAC-hs the priority of flows in the MAC-d. The priority of
MAC-d flows are indicated by higher layers, and they depend totally on the QoS / application requested
by each user. The MAC-d has already indicated to the MAC-hs in the NBAP message the priority of flows
in the MAC-d. So, the MAC-d flows are passed on to the MAC-hs at the Node B through the HS-DSCH
framing protocol. Based on the priority of flows, the MAC-hs stores this data in priority queues. There can
be several priority queues with a unique queue identifier. Now, the MAC-hs forwards the scheduled data
through the HARQ entity, which keeps track of different HARQ processes.
HSDPA User Data Flow
4-68
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSDPA User Data FlowHSDPA User Data FlowRNC
RLC AM/UM
PDCP
User data from SGSN
DTCH 1 DTCH 2 DTCH 3 DCCH
C/T MUX
MAC-d flows
MAC-d
Node B
MAC-hs
Priority Queue Distribution
Priority Queue Distribution
PriorityQueue
PriorityQueue
PriorityQueue
PriorityQueue
HARQ ENTITY
HS-DSCH
Physical Layer Functions
MAC—hs Queue ID, TSN
Uu
Iub Framing Protocol
4-69
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The HARQ entity at the Node B runs several HARQ processes in parallel. The MAC-hs adds its header,
and then forwards it to the physical layer through the HS-DSCH transport channel. The MAC-hs header
contains important information such as the queue identifier and Transmission Sequence Number (TSN).
The TSN is incremented for every MAC-hs PDU transmitted to its peer entity. One HS-DSCH transport
channel is capable of transmitting several priority classes of user data. Only one priority class can exist per
TTI. The user data is now channel-coded (turbo coding 1/3) and then divided into 3 streams of data by the
physical layer HARQ. The physical layer HARQ now transmits the subpackets based on the RV version
signaled previously on the HS-SCCH. The RV version can have varying parameters depending on HARQ
retransmission techniques. The HARQ retransmission techniques can be classified into chase combining,
partial incremental redundancy and full incremental redundancy. If 16QAM modulation is used,
constellation bit rearrangement is also applied. The constellation bit rearrangement is part of the RV
parameter. The HARQ bits are mapped to physical channel HS-PDSCH. Based on information signaled
on the HS-SCCH, the Node B physical layer forms the transport block, multi-spreads the HS-PDSCH data
with OVSF codes of spreading factor 16, and then spreads it with the cell-specific scrambling code of the
serving HS-PDSCH cell.
The UE receives the data and performs physical layer functions such as demodulation based on
modulation type, descrambling, de-spreading of OVSF codes, and the HARQ ACK/NACK. Then it
forwards the data to the MAC-hs layer at the UE. The re-ordering queue distribution function at the MAC-
hs routes the MAC-hs PDUs to the correct re-ordering buffer based on the Queue ID. Once the MAC-hs
PDUs are stored in the re-ordering buffer, the re-ordering entity reorders received MAC-hs PDUs
according to the received Transmission Sequence Number (TSN). The TSN is unique per priority queue.
Once the data stored in the re-ordering buffer is reordered, the MAC-hs disassembles the MAC-hs header
and forwards the MAC-d flows to the MAC-d layer. The MAC-d de-multiplexes the MAC-d PDUs from
different MAC-d flows into their corresponding logical channels. The data belonging to different logical
channels is sent to the RLC layer. The RLC checks for any errors if operating in RLC–AM mode. If errors
are found, it may request a retransmission from the RLC peer entity at the RNC. The RLC then assembles
the RLC SDUs and forwards them to the PDC. The PDCP performs decompression and passes the
payload to the applications layer.
HSDPA User Data Flow (continued)
4-70
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSDPA User Data Flow HSDPA User Data Flow (continued)(continued)RNC
RLC AM/UM
PDCP
User data from SGSN
DTCH 1 DTCH 2 DTCH 3 DCCH
C/T MUX
MAC-d flows
MAC-d
Node B
MAC-hs
Priority Queue Distribution
Priority Queue Distribution
PriorityQueue
PriorityQueue
PriorityQueue
PriorityQueue
HARQ ENTITY
HS-DSCH
Physical Layer Functions
MAC—hs Queue ID, TSN
Uu
Iub Framing Protocol
4-71
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The UE receives the data and performs physical layer functions, such as demodulation based on
modulation type, descrambling, de-spreading of OVSF codes, and HARQ ACK/NACK. Then it forwards
the data to the MAC-hs layer at the UE. The re-ordering queue distribution function at the MAC-hs, routes
the MAC-hs PDUs to the correct re-ordering buffer based on the Queue ID. Once the MAC-hs PDUs are
stored in the re-ordering buffer, the re-ordering entity reorders received MAC-hs PDUs according to the
received Transmission Sequence Number (TSN). The TSN is unique per priority queue. Once the data
stored in the re-ordering buffer is reordered, the MAC-hs disassembles the MAC-hs header and forwards
the MAC-d flows to the MAC-d layer. The MAC-d de-multiplexes the MAC-d PDUs from different
MAC-d flows into their corresponding logical channels. The data belonging to different logical channels is
sent to the RLC layer. The RLC checks for any errors if operating in RLC–AM mode. If errors are found,
the UE may request for a retransmission from the RLC peer entity at the RNC.
HSDPA Traffic Flow
4-72
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSDPA Traffic FlowHSDPA Traffic FlowUE Node B
MAC-hs
Re-ordering Queue Distribution
Re-orderingBuffer
Priority Queue Distribution
Priority Queue Distribution
PriorityQueue
PriorityQueue
PriorityQueue
PriorityQueue
HARQ ENTITY
HS-DSCH
Physical Layer Functions
Re-orderingBuffer
MAC–d Flow
C/T MUX
DTCH 1 DTCH 2 DTCH 3 DCCH
RLC AM/UM
ApplicationsPDCP
MAC-hs Queue ID,
TSN
MAC–d Flow
UuPhysical Layer Functions
4-73
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
This figure depicts the usage of HSDPA channels among R99 channels. As stated before, HSDPA is an
evolution of R99. So, the UMTS R99 channels and HSDPA channels co-exist.
Since UMTS can support multiple services simultaneously, it is required to have both types of channels
simultaneously.
In addition to the above, the R00 uplink and downlink channels still support soft handover during an
HSDPA call. A UE in an HSDPA transaction can only be served by a single serving cell / Node B. Also,
no power control exists in the downlink for an HSDPA call. During soft handover, all active set Node Bs
can send power control commands to the UE. These power control commands, TPC bits, are carried by the
DPCCH in the downlink from all active set Node Bs. The power control is done on the DPDCH /
DPCCH. The HS-DPCCH power is always relative to the DPCCH. So, by varying the power of the
DPCCH, HS-DPCCH power is also varied. The offset to be used between the DPCCH and HS-DPCCH is
signaled during the radio bearer setup message.
Channel Usage
4-74
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Channel UsageChannel Usage
UE
Serving Node B
Other “Active”Node Bs
CQI/ACK-NACK
HS-DPCCH(HSDPA)
Voice, Data, Signaling/TCI, Pilot, TPC
DPCH (non-HSDPA)
HSDPA and R99 server for the UE
DPCH
DPDCH/DPCCH
DPCH
HS-SCCH/HS-PDSCHHSDPA Control/data
R99 Server for
this UE
R99 Server for
this UE
DPDCH/DPCCH
Voice, Data, Signaling/TFCI, Pilot, TPC
DPDCH/DPCCH
4-75
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Three types of reconfiguration methods are used in UMTS. All three methods have been enhanced at the
RRC to support HSDPA.
1. Radio Bearer Reconfiguration
Radio bearer reconfiguration is required when the following changes occur:
• When the Quality Of Service (QoS) changes, such as adding a new service to the old
service. This is very common in UMTS, and reconfiguration happens frequently
throughout the life cycle of a call. In HSDPA, there also can be multi services like circuit-
switched calls with HSDPA. So, if a circuit-switched call is already established and an
HSDPA call is added to the existing circuit-switched call, Radio Bearer Reconfiguration
is performed by the RRC.
• Change of RLC content
• Change of TFS/TFCS
• Assignment/release of physical channels
2. Transport Channel Reconfiguration
The transport channel reconfiguration is required when the following changes occur:
• Changes in traffic volume
• Changes in TFS
• Use of a new transport channel
• Need to change physical channel bandwidth
A good example of transport channel reconfiguration is during an Inter-Node B HS-DSCH hard
handover.
Reconfiguration Types and Functions
4-76
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Reconfiguration Types and FunctionsReconfiguration Types and Functions
Radio Bearerreconfiguration
Transport channel
Reconfiguration
Physical channelReconfiguration
• Change of QoS• Change of RLC content • Change of TFS/TFCS• Assignment/release of
physical channels
• Changes in traffic volume
• Changes in TFS• Use of new transport
channel• May change physical
• Changes in RRC states• changes in DL CC• No transport channel
type switching
Reconfiguration
4-77
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
3. Physical Channel Configuration
Physical channel reconfiguration can be needed when the following changes occur:
• Changes in RRC states such as moving from a cell DCH to Cell FACH state
• Changes in DL Channelization codes
• When transport channel type switching happens, physical channel reconfiguration cannot
be performed
Good examples of physical channel reconfiguration are Intra-Node B handovers in HSDPA and
sector switching within a Node B.
Reconfiguration Types and Functions (continued)
4-78
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Reconfiguration Types and FunctionsReconfiguration Types and Functions(continued)(continued)
Radio Bearerreconfiguration
Transport channel
Reconfiguration
Physical channelReconfiguration
• Change of QoS• Change of RLC content • Change of TFS/TFCS• Assignment/release of
physical channels
• Changes in traffic volume
• Changes in TFS• Use of new transport
channel• May change physical
• Changes in RRC states• changes in DL CC• No transport channel
type switching
Reconfiguration
4-79
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The following example shows a message sequence flow explaining the setup of an HS-DSCH. For
example, the UE is already on a CS call, and now it wants to download a video streaming application. The
UE is an HSDPA-capable mobile, and the UTRAN may provide HSDPA resources for this service. The
UE is in a cell_ DCH state. In case no RL has already been established, the Radio Link Setup procedure is
used instead of the Radio Link Reconfiguration procedure. In this case, the RL has been already
established.
1. The RNC receives a RANAP RAB Assignment Request message from the SGSN requesting a
specific QoS. The RNC requests the Node B to prepare for configuration or reconfiguration of the
HS-DSCH.
2. To channel-switch to the HS-DSCH, the radio link, which carries the HS-DSCH, has to be
reconfigured. The SRNC initiates a radio link reconfiguration by sending the Radio Link
Reconfiguration Prepare message to the Node B.
Parameters: HS-DSCH information and an SRNC-selected HS-PDSCH RL ID
HS-DSCH information contains all MAC-d details, CQI parameter and ACK/NACK information.
3. The Node B configures resources for the HS-DSCH and responds with the NBAP Radio Link
Reconfiguration Ready message.
Parameters: The HS-DSCH Information Response which contains HS-SCCH channelization
codes, HARQ processes, etc.
4. The NBAP Radio Link Reconfiguration Commit message is sent from the SRNC to the Node B.
5. The RNC initiates setup of Iub data transport bearers using the ALCAP protocol. This request
contains the AAL2 binding identity to bind the Iub data transport bearer to the HS-DSCH.
6. The RNC sends the RRC Radio Bearer Reconfiguration message to the UE to establish the
requested HS-DSCH.
HS-DSCH Configuration
4-80
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--DSCH ConfigurationDSCH ConfigurationUE RNC GGSNSGSN
1. RAB Assign. Req.
Node B
2. Radio Link Reconfig Prepare
3. Radio Link Reconfig Ready
4. Radio Link Reconfig Commit
5. Iub Trans Bearer Setup6. Radio Bearer Reconfiguration
7.Radio Bearer Reconfig Comp
8. HS-DSCH Capacity Request
9. HS-DSCH Capacity Allocation
10. Information Transfer11.HS-SCCH/HSPDSCH Data
• Change in QoS can add/del MAC-d flow and also change priority queues
QoS modification
4-81
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
7. The UE replies with the RRC Radio Bearer Reconfiguration Complete message. At this point, the
HS-DSCH transport channel has been set up, and it is assumed that the MAC-hs in the Node B
has already been configured earlier to have access to a pool of HS-PDSCH resources for HS-
DSCH scheduling. The RNC also sends a RAB Assignment Response to the SGSN.
8. As soon as the RNC detects the necessity to send HS-DL data on one HS-DSCH, it sends an HS-
DSCH capacity request control frame within the HS-DSCH frame protocol to the Node B.
Parameters: Common Transport Channel Priority Indicator and User Buffer Size.
9. The Node B determines the amount of data (credits) that can be transmitted on the HS-DSCH and
reports this information back to the RNC in a HS-DSCH capacity allocation control frame in the
HS-DSCH frame protocol.
Parameters: Common Transport Channel Priority Indicator, HS-DSCH credits, HS-DSCH
interval, HS-DSCH repetition period, and maximum MAC-d PDU length.
10. The RNC starts sending DL data to the Node B. This is done via the two HS-DSCH frame
protocols on the Iub interface. The Node B schedules the DL transmission of DL data on the HS-
DSCH, which includes allocation of PDSCH resources.
11. The Node B transmits the control information for the concerned UE using the HS-SCCH. The
Node B then sends the HS-DSCH data to the UE on the HS-PDSCH(s).
HS-DSCH Configuration (continued)
4-82
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSHS--DSCH ConfigurationDSCH Configuration (continued)(continued)UE RNC GGSNSGSN
1. RAB Assign. Req.
Node B
2. Radio Link Reconfig Prepare
3. Radio Link Reconfig Ready
4. Radio Link Reconfig Commit
5. Iub Trans Bearer Setup6. Radio Bearer Reconfiguration
7.Radio Bearer Reconfig Comp
8. HS-DSCH Capacity Request
9. HS-DSCH Capacity Allocation
10. Information Transfer11.HS-SCCH/HSPDSCH Data
• Change in QoS can add/del MAC-d flow and also change priority queues
QoS modification
4-83
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Radio bearer release is also enhanced in RRC to support HSDPA. Radio bearer release can simultaneously
release a service and reconfigure another service if two services are accessed by the UE simultaneously.
1. The UE has finished downloading an application using HSDPA. So, the UE sends a Deactivate
PDP Context Request, which is a Direct Transfer message. It sends the APN, IP address, QoS
negotiated, etc. to the RNC.
2. The RNC forwards this message as a RANAP Direct Transfer Deactivate PDP Context message
to the SGSN. It sends the GTP TE-ID along with the above parameters.
3-4. The SGSN requests the GGSN to delete the tunnel by sending a Delete PDP Context Request
established for this APN, IP address and QoS. The GGSN talks to the external network and
requests it to release the connection. The GGSN responds to the SGSN with a Delete PDP
Context Response.
5. The SGSN sends a RAB Release Request to delete the RAB assigned on the Iu and radio bearer
assigned to the UE for this QoS and application.
6. The RNC requests the Node B to prepare release of the HS-DSCH carrying the radio access
bearer (Radio Link Reconfiguration Prepare).
Parameters: Delete MAC-d flows HS-PDSCH RL ID
7. The Node B notifies the RNC that release preparation is ready (Radio Link Reconfiguration
Ready).
8. The NBAP Radio Link Reconfiguration Commit message is sent from the RNC to the Node B.
9. The RRC Radio Bearer Release message is sent by the RNC to the UE.
Parameters: HS-DSCH information such as HS-SCCH codes, MAC- d flows to delete, priority
queues, etc.
10. The UE sends the RRC Radio Bearer Release Complete message to the SRNC.
Radio Bearer Release - HSDPA
4-84
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Radio Bearer Release Radio Bearer Release -- HSDPAHSDPAUE RNC GGSN
1. UL DT (DeActivate PDP CTX Req.) 2. DT (Deact. PDP CTX Req.)
SGSN
3.Delete PDP CTX Req.
4. Delete PDP CTX Res
Node B
5. RAB Release Request
6. RL Reconfig. Prep.
7. RL Reconfig. Ready
9. Radio Bearer Release
10. Radio Bearer Release Comp
8. RL Reconfig. Commit
11. Iub Trans Bearer Release
4-85
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
11. Unused resources in the RNC and the Node B (Serving RNS, if any) are released. The RNC
initiates release of the Iub (serving RNS) data transport bearer using the ALCAP protocol.
12. The SRNC acknowledges the release of the radio access bearer with the Radio Access Bearer
Release Response message.
Radio Bearer Release - HSDPA (continued)
4-86
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Radio Bearer Release Radio Bearer Release -- HSDPA HSDPA (continued)(continued)UE RNC GGSN
1. UL DT (DeActivate PDP CTX Req.) 2. DT (Deact. PDP CTX Req.)
SGSN
3.Delete PDP CTX Req.
4. Delete PDP CTX Res
Node B
5. RAB Release Request
6. RL Reconfig. Prep.
7. RL Reconfig. Ready
9. Radio Bearer Release
10. Radio Bearer Release Comp
8. RL Reconfig. Commit
11. Iub Trans Bearer Release
4-87
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The HS-DSCH is only allocated in the downlink for HSDPA users. There are two aspects to managing
mobility when using the HS-DSCH.
The first is related to the signaling aspects of managing the neighbor list when using the HS-DSCH. The
second category is related to mobility management when the UE is receiving traffic on the HS-DSCH.
When a mobile station is involved in a packet data session using the HS-DSCH, it may also be configured
to monitor multiple pilots of nearby base stations. This is the same mechanism used in UMTS R99 systems,
where the mobile station is monitoring all the base stations in the neighbor list. The Node B and UE
communicate to constantly add, delete or change the members of the active set. The base stations may be
moving between active, neighbor and candidate sets as they monitor and measure pilot channel strength.
Therefore, as part of using the HS-DSCH, even though there is only one HS-DSCH that is actively
transmitting data, the mobile station is always monitoring all members of the active set. All the existing
mechanisms used in UMTS R99 are used here as well to manage the active set.
When the mobile station is actively receiving traffic on the HS-DSCH, the situation is different. The
mobile station receives packet data from one base station on the HS-DSCH. The mobile station receives
packet data from the base station that it hears the best. This is determined by measuring the Carrier-to-
Interference (C/I) ratio of the pilot channels of the base stations in the active set.
Multiple HS-DSCHs are not used in the downlink for several reasons.
• Multiple HS-DSCH channels from Node Bs require coordination and this renders CQI
measurements invalid. Such a scenario might significantly reduce the achievable throughput of the
system.
• The HS-DSCH uses available power and this may be quite different in the two Node Bs/cells
• The CQI measurements from multiple cells is required
Handover Procedures While Using the HS-DSCH
4-88
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Handover Procedures While Using Handover Procedures While Using the HSthe HS--DSCHDSCH
HS-DSCH
Measurements TrafficCreate Active, Neighbor and
Monitored Sets
• Transmission from (one cell, one Node B)
• Serving Cell part ofthe Active Set
4-89
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The diagram shows how the UE manages the neighbor list in HSDPA system when using the HS-DSCH.
The basic handover support mechanisms remain the same in HSDPA as in UMTS R99. The RNC sends a
measurement control message in which the RNC provides the neighbor list and the reporting criteria to the
UE. It also specifies the conditions under which the UE should send the Measurement Report message.
Periodic reporting is also supported. One of the reporting events is the “Change of Best Cell.” Since the
HS-DSCH transmission occurs only from a single cell, layer 3 signaling messages are used.
In our example, the mobile station currently is being served by Node B A. So, the UE belongs to only one
of the radio links assigned to the UE, the serving HS-DSCH radio link. The cell associated with the
serving HS-DSCH radio link is defined as the serving HS-DSCH cell.
There must be synchronization between the UE and UTRAN indicating when transmission and reception
is stopped and re-started. Two possibilities for a serving HS-DSCH cell change exist:
1. A synchronized serving HS-DSCH cell change defines the start and stop of HS-DSCH
transmission and reception at a certain time typically selected by the network.
2. An unsynchronized serving HS-DSCH cell change defines the start and stop of HS-DSCH
transmission and reception is performed "as soon as possible" (stated by UE performance
requirements) at either side.
Handover Measurement Management
4-90
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Handover Measurement ManagementHandover Measurement Management
UE
Measurement Control
Measurement Report
Physical Channel Reconfiguration(Intra-Node B Handover)
Transport Channel Reconfiguration(Inter-Node B Handover)
Node B
Node B
UE
Neighbor List
Cell ACell B
…
Measurement Report
Intra-Node B & Inter-Node B Hard
Handovers for HS-PDSCHs
Synchronized Non synchronized
4-91
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The serving HS-DSCH cell change may also be categorized with respect to the serving HS-DSCH Node
B.
The UE might, while monitoring the neighbor list, notice that another Node B / cell is received strongly by
measuring the pilot strength. The UE transmits a Measurement Report message containing intra-frequency
measurement results triggered by the event 1D “Change of Best Cell“ to the RNC:
1. Intra-Node B Hard Handover: The source and target HS-DSCH cells are both controlled by the
same Node B. The serving HS-DSCH Node B is not changed.
In the case of an intra-Node B hard handover, the RNC then decides to change the physical
channels of the UE. Therefore, the RNC responds with a Physical Channel Reconfiguration or
Transport Channel Reconfiguration message that instructs the UE to the new cell/sector and the
new set of spreading factor codes that will be used for the SCCH and HS-DSCH.
2. Inter-Node B Hard Handover: The Node B controlling the target HS-DSCH cell is different
from the Node B controlling the source HS-DSCH cell.
In the case of an inter-Node B hard handover, the RNC sends a Transport Channel
Reconfiguration message on the old configuration. This message indicates the configuration after
handover, both for DCH and HS-DSCH. The Transport Channel Reconfiguration message
includes a flag indicating that the MAC-hs entity in the UE will be reset. The message also
includes an update of transport channel related parameters for the HS-DSCH in the target HS-
DSCH cell.
Handover Measurement Management (continued)
4-92
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Handover Measurement Management Handover Measurement Management (continued)(continued)
UE
Measurement Control
Measurement Report
Physical Channel Reconfiguration(Intra-Node B Handover)
Transport Channel Reconfiguration(Inter-Node B Handover)
Node B
Node B
UE
Neighbor List
Cell ACell B
…
Measurement Report
Intra-Node B & Inter-Node B Hard
Handovers for HS-PDSCHs
Synchronized Non synchronized
4-93
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
If any of the primary CPICHs within the reporting range become better than the previously best primary
CPICH, the UE sends a measurement report if event 1D is ordered by the UTRAN.
The hysteresis parameter may be connected with each reporting event. The value of the hysteresis is given
to the UE in the reporting criteria field of the Measurement Control message.
In the example shown in the slide, the hysteresis ensures that the event 1D (primary CPICH 2 becomes the
best cell) is not reported until the difference is equal to the hysteresis value. The fact that the primary
CPICH 1 becomes best afterward is not reported at all in the example since the primary CPICH 1 does not
become sufficiently better than the primary CPICH 2.
HSDPA - Best Cell Change
4-94
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSDPA HSDPA -- Best Cell ChangeBest Cell Change• Hysteresis
– Send measurement report only when the difference of signal strengths equals the hysteresis value
– Best cell change - 1D event
CPICH 1
CPICH 2Hysteresis
Hysteresis
Reporting event 1D
Time
Measurementquantity
4-95
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The slide describes intra-Node B synchronized handovers or sector switching of the UE. Our example
consists of a UE with an active set that includes sectors 1, 2 and 3.
Sector 1 is the serving HSDPA cell with the HS-SCCH and HS-PDSCH in the downlink and the HS-
DPCCH in the uplink. The other R99 channels DPCCH/DPDCH in both uplink and downlink in sectors 1,
2 and 3 still exist since support for soft handoff in uplink and downlink for regular R99 services still has to
be supported. So, when event 1D is triggered, in this example sector 3 becomes the best cell. Intra-Node B
handover is triggered from sector 1 to sector 3. The system reconfigures sector 3 with HSDPA uplink and
downlink channels and releases sector 1. Other R99 channels still exist without change.
Intra-Node B – Sync (Sector Switching)
4-96
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
IntraIntra--Node B Node B –– Sync (Sector Switching)Sync (Sector Switching)
DPCCH/DPDCH
DPCCH
/DPD
CH
HS-SCCH/HS-DPCCH
DPCCH/DPD
CH
Active Set: Sectors 1, 2, and 3Switches to sector 3
Sector 1 Sector 3Sector 2
Source Target
4-97
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
This slide depicts the intra-Node B synchronized handover message sequence. The word synchronized
means that the activation time is sent to the UE which informs the UE about the time at which it should
switch over to the target cell/ sector. In this example, it is assumed that the HS-DSCH transport channel
and radio bearer parameters do not change. If the transport or radio bearer parameters are used, the serving
HS-DSCH cell change needs to be executed by the transport channel reconfiguration procedure or radio
bearer configuration procedure
1. The UE sends a measurement report E (1D) to the SRNC via the DCCH to indicate a better cell.
The measurement report criteria can be P-CPICH (Ec/Io).
2. The SRNC decides to perform a best cell change to sector 1D.
3. The SRNC requests the serving HS-DSCH Node B to perform a synchronized radio link
reconfiguration using the NBAP Synchronized Radio Link Reconfiguration Prepare message.
Parameters provided include HS-DSCH information, the HS-DSCH RNTI and the HS-PDSCH
RL ID.
4. The serving HS-DSCH Node B returns an NBAP Synchronized Radio Link Reconfiguration
Ready message. Parameters carried include the HS-DSCH information response.
5. The SRNC now transmits NBAP Radio Link Reconfiguration Commit message to the Node B.
This message provides the activation time in the form of a Connection Frame Number (CFN).
6. The SRNC transmits the RRC Physical Channel Reconfiguration message to the UE. Parameters
provided include activation time, MAC-hs reset indicator, serving HS-DSCH RL ID, HS-SCCH
set information and the H-RNTI.
7. At the indicated activation time, the UE stops receiving the HS-DSCH in the source cell and starts
HS-DSCH reception in the target cell. The UE then returns a Physical Channel Reconfiguration
Complete message via the DCCH.
Intra-Node B – Sync (Sector Switching)
4-98
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
IntraIntra--Node B Node B –– Sync (Sector Switching)Sync (Sector Switching)S - NB
1
SRNC
23Active set sectors 1, 2, 3HSDPA serving cell is 1
1.Measurement Report (event 1D)
3.RL Reconfig. Prepare
4. RL Reconfig. Ready
5. RL Reconfig. Commit
6.Physical Channel Reconfiguration
7. Physical Channel Reconfiguration Complete
2. Decision for best cell change to sector 3
Start TX/RX at target Stop TX/RX in source at given activation time
4-99
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
This slide illustrates a synchronized inter-Node B serving HS-DSCH cell change in combination with a
hard handover. This is possible when fast handovers of both the DCH and HS-DSCH are required. To
trigger the hard handover, the SRNC sends a Transport Channel Reconfiguration message on the old
configuration. This message takes care of both the DCH and HS-DSCH configurations after handover.
The Transport Channel Reconfiguration message includes a flag indicating that the MAC-hs entity in the
UE shall be reset. This message also includes the transport channel parameters for the HS-DSCH in the
target HS-DSCH cell.
1. The UE sends a measurement report event 1D to the SRNC on the DCCH to indicate a better cell.
2. The SRNC decides that there is a need for a hard handover with the serving HS-DSCH cell
change to sector 1, T-NB
3. The SRNC transmits a Radio Link Setup Request message to the target Node B.
4. The target Node B allocates resources, starts physical layer reception on the DPCH on a new radio
link and responds with the NBAP Radio Link Setup Response message. It provides the HS-DSCH
Information Response.
5. The SRNC initiates setup of a new Iub data transport bearer for the DCH using the ALCAP
protocol. This request contains the AAL2 binding ID to bind the Iub data transport bearer to the
DPCH.
6. The SRNC requests the source HS-DSCH Node B to perform a Synchronized Radio Link
Reconfiguration Prepare, removing its HS-DSCH resources for the source HS-DSCH radio link.
Parameters include HS-DSCH information, an allocated H-RNTI and the HS-PDSCH RL ID.
7. The source HS-DSCH Node B responds with a Synchronized Radio Link Reconfiguration Ready.
Parameters provided include the HS-DSCH Information Response.
8. The SRNC transmits an NBAP Radio Link Reconfiguration Commit to the source cell indicating
when the MAC-hs will stop sending HS-DSCH data blocks. At the indicated activation time, the
source Node B stops and the target HS-DSCH Node B starts transmitting on the HS-DSCH to the
UE. Parameters in this message include activation time in the form of a CFN.
Inter-Node B – Sync Hard Handover
4-100
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
InterInter--Node B Node B –– Sync Hard HandoverSync Hard HandoverS - NB
1
SRNC
.
23Active set sectors1, 2, 3HSDPA Serving cell is (1, S-NB)
1.Measurement Report (event 1D)
3. RL Setup Request
4. RL Setup Response
T - NB1
Start TX
Start TX
5. Iub Bearer - DCH
6. RL Reconfiguration Prepare
7. RL Reconfiguration Ready
8. RL Reconfiguration Commit
9. RL Reconfig Prepare
10. RL Reconfig Ready
2. Decision for best cell change to sector 1,T-NB
4-101
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
9. Now, the SRNC requests the target HS-DSCH Node B to perform a Synchronized Radio Link
Reconfiguration Prepare. This message informs the Node B to add HS-DSCH resources of the
target HS-DSCH radio link.
10. The Node B responds with an NBAP Radio Link Reconfiguration Ready. It consists of an HS-
DSCH Information Response.
Inter-Node B – Sync Hard Handover (continued)
4-102
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
InterInter--Node B Node B –– Sync Hard Handover Sync Hard Handover (continued)(continued)S - NB
1
SRNC
23Active set sectors1, 2, 3HSDPA Serving cell is (1, S-NB)
1.Measurement Report (event 1D)
3. RL Setup Request
4. RL Setup Response
T - NB1
Start TX
Start TX
5. Iub Bearer - DCH
6. RL Reconfiguration Prepare
7. RL Reconfiguration Ready
8. RL Reconfiguration Commit
9. RL Reconfig Prepare
10. RL Reconfig Ready
2. Decision for best cell change to sector 1,T-NB
4-103
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
11. The SRNC initiates the setup of a new Iub data transport bearer using an ALCAP protocol. This
request contains the AAL2 Binding ID to bind the Iub data transport bearer to the HS-DSCH.
12. The HS-DSCH transport bearer to the target HS-DSCH Node B is established. The SRNC now
transmits an NBAP Radio Link Reconfiguration Commit message to the Node B. The parameters
sent in this message include the activation time in the form of a CFN.
13. The SRNC transmits an RRC message Transport Channel Reconfiguration to the UE. Parameters
provided include activation time, the MAC-hs Reset Indicator, serving HS-DSCH radio link
indicator, HS-SCCH set information and the H-RNTI.
14. At the indicated activation time, the UE initiates establishment of the DPCH in the target cell.
When physical layer synchronization is established in the target cell, the UE starts DPCH
reception, and also starts transmission and reception of the HS-DSCH in the target cell. The UE
responds with a Transport Channel Reconfiguration Complete message.
15. The SRNC will initiate the procedure of Radio Link deletion Request to the source Node B to de-
allocate radio resources (DPCH and HS-PDSCH’s )
16. The source Node B releases the HS-DSCH and DCH resources and returns a Radio Link Deletion
response to the SRNC. Finally the DCH and HS-DSCH ALCAP transport bearers are released.
Inter-Node B – Sync Hard Handover
4-104
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
InterInter--Node B Node B –– Sync Hard HandoverSync Hard HandoverS - NB
1
SRNC
.
23
12. RL Reconfig Commit
T - NB1
13. DCCH Transport Channel Reconfiguration sent on old config
11. Iub bearer HS-DSCH
Start TX/RX at Target Stop TX/RX in source at given activation time
14. Transport Channel Reconfiguration Complete
15. RL Deletion Request16. RL Deletion ResponseStop TX/RX
4-105
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
This figure depicts an inter-Node B serving HS-DSCH cell change performed after an active set update. In
this example, a new radio link is added that is different from the source Node B and belongs to a target
Node B. The cell added to the active set becomes the serving HS-DSCH cell in the second step. The entire
procedure consists of an ordinary Active Set Update procedure in the first step and a synchronized serving
HS-DSCH cell change in the second step. Please refer specs 25.308.
1. The UE transmits a Measurement Report message containing intra-frequency measurement
results.
2. Based on the received measurement reports and/or load control algorithms, the SRNC determines
the need for the combined radio link addition and serving HS-DSCH cell change, and sends a
Radio Link Setup message to the T-NB.
3. The T-NB responds with a Radio Link Setup Response message to the SRNC.
4. The SRNC establishes the new radio link in the target Node B for the dedicated physical channels
and transmits an Active Set Update message to the UE. The message includes the necessary
information for establishment of the dedicated physical channels in the added radio link (but not
the HS-PDSCH).
5. When the UE has added the new radio link, it returns an Active Set Update Complete message.
The SRNC will now carry on with the next step of the procedure, which is the serving HS-DSCH cell
change. The target HS-DSCH cell is the newly added radio link, only including dedicated physical
channels. For the synchronized serving HS-DSCH cell change, both the source and target Node Bs are
first prepared for execution of the handover at the activation time.
6. The SRNC requests the S-Node B to perform a Synchronized Radio Link Reconfiguration
Prepare, removing its HS-DSCH resources for the source HS-DSCH radio link. Parameters
include HS-DSCH information, the allocated H-RNTI and the HS-PDSCH RL ID.
Cell Change after Active Set Update
4-106
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Cell Change after Active Set UpdateCell Change after Active Set UpdateS - NB
1
SRNC
.
23T - NB
1
4. Active Set Update
1. Measurement Report
2. RL Setup Request
3. RL Setup Response
5. Active Set Update Complete
6. RL Reconfiguration Prepare
7. RL Reconfiguration Ready
8. RL Reconfiguration Commit
4-107
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
7. The source HS-DSCH Node B responds with the synchronized Radio Link Reconfiguration
Ready message. Parameters provided include the HS-DSCH Information Response.
8. The SRNC transmits an NBAP Radio Link Reconfiguration Commit message to the S-NB,
indicating when the MAC-hs will stop sending HS-DSCH data blocks. At the indicated activation
time, the source Node B stops and the target HS-DSCH Node B starts transmitting on the HS-
DSCH to the UE. Parameters in this message include activation time in the form of a CFN.
Cell Change after Active Set Update (continued)
4-108
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Cell Change after Active Set Update Cell Change after Active Set Update (continued)(continued)
S - NB1
SRNC
.
23T - NB
1
4. Active Set Update
1. Measurement Report
2. RL Setup Request
3. RL Setup Response
5. Active Set Update Complete
6. RL Reconfiguration Prepare
7. RL Reconfiguration Ready
8. RL Reconfiguration Commit
4-109
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
9. Now the SRNC requests the T-Node B to perform a synchronized Radio Link Reconfiguration
Prepare. This message informs the Node B to add HS-DSCH resources to the target HS-DSCH
radio link.
10. The Node B responds with an NBAP Radio Link Reconfiguration Ready. It consists of an HS-
DSCH Information Response.
11. The SRNC now transmits an NBAP Radio Link Reconfiguration Commit message to the Node B.
The parameters sent in this message include the activation time in the form of a CFN.
12. The SRNC then sends a Transport Channel Reconfiguration message, which indicates the target
HS-DSCH cell and the activation time to the UE. The message may also include a configuration
of transport channel-related parameters for the target HS-DSCH cell, including an indication to
reset the MAC-hs entity, and a status report for each RLC entity associated with the HS-DSCH
that should be generated.
Thus, at the indicated activation time the transmission from the target HSDSCH cell is started, and
the transmission from the source Trx is stopped.
13. When the UE has completed the serving HS-DSCH cell change it returns a Transport Channel
Reconfiguration Complete message to the SRNC.
Inter-Node B – Cell Change after Active Set Update
4-110
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
InterInter--Node B Node B –– Cell Change after Active Cell Change after Active Set UpdateSet Update
S - NB1
SRNC
23T - NB
1
12. Transport Channel Reconfiguration
10. RL Reconfig Ready
11. RL Reconfig Commit
9. RL Reconfig Prepare
Start Trx for HSDSCH in the target HSDSCH cell, stop Trx in the source HSDSCH cell at the given activation time
13. Transport Channel Reconfiguration Complete
4-111
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
To perform the cell re-selection operation, the UE first needs to know the necessary system information
about the system it is camping on as well as the systems that are in the surrounding geographical area – the
neighbor cells.
First, the UE searches for the strongest cell and performs the PLMN selection and cell selection. Once it
synchronizes with the current cell, it monitors the Broadcast Channel (BCH) and gathers information
about the current cell and its neighbors from the System Information Blocks (SIB). A SIB groups together
system information of the same nature. The SIBs are sent on the BCH periodically. The UMTS
specification describes over 15 different types of SIBs. The SIBs that carry information relevant for cell
selection and re-selection are SIBs 1, 2, 3, 4,5, 11 and 12.
For example, SIB 1 carries various parameters related to Non Access Stratum (NAS) and the core
networks (CN). It also specifies various constants and timers the UE has to use during various operations
such as cell re-selection. Various cell selection and re-selection criteria are specified in SIB 3 (for idle
mode) and SIB 4 (for connected mode). In addition, SIBs 11 and 12 also describe parameters related to
specific radio measurements. The system information block type 5 contains parameters for the
configuration of the common physical channels in the cell.
In R6, SIB 5 has been modified to indicate whether it is an “HSDPA-capable cell”, which means that the
UE may consider this cell as part of the HSDPA coverage area.
The UTRAN broadcasts an HSDPA cell indicator in SIB block 5 to indicate whether the cell is HSDPA-
capable or not.
HSDPA Cell Indicator - R6
4-112
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
HSDPA Cell Indicator HSDPA Cell Indicator -- R6R6
UE
Node B
SIB 5Configuration of common physical
channel parametersHSDPA cell indicator
4-113
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Most of the parameters in the RRC connection establishment procedure in R6 are the same as in R5, but a
few parameters carried by these messages indicate HSDPA support. The enhancements in R6 include:
1. RRC Connection Request sent by the UE
• Domain Indicator: Indicates whether the Core Network (CN) is Circuit-Switched (CS)
or Packet-Switched (PS). In an HSDPA data call, the call is routed by the RNC to the
SGSN in the PS domain through the Iu Interface.
• Access Stratum Release Indicator: Should support R6 also
• UE Capability Indication: Sent by the UE to inform the RNC about its indicating its
HSDPA functionality
2. RRC connection setup sent by UTRAN
• H-RNTI Assignment: H-RNTI is the HSDPA UE Identity. The H-RNTI is an ID for the
UE that will be doing HSDPA within a cell. The H-RNTI variable is a 16-bit string that
stores the assigned H-RNTI for this UE when in the CELL-DCH state and a HS-DSCH
transport channel has been allocated. It gets cleared when leaving the UTRA RRC-
connected mode.
• Downlink HS-PDSCH: The HS-PDSCH is a new channel in HSDPA that carries high-
speed packet data traffic. It is a shared channel across all users requesting HSDPA
specific high-speed packet data services.
Downlink HS-PDSCH includes the information parameters such as HS-SCCH control
information, which consists of the DL Scrambling code to be applied for HS-SCCH, HS-
SCCH channelization codes, the maximum number of Dedicated Physical Data Channels
(DPDCH) from which HS-DPCCH channelization codes are derived by the UE and
measurement feedback information that is used for the channel quality indication (CQI)
procedure in the physical layer on the serving HS-DSCH radio link.
3. The RRC Connection Complete message from the UE may carry UE radio access capability
parameters whose contents are the same as in the R5 RRC Connection Complete message.
RRC Connection Enhancement - R6
4-114
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
RRC Connection Enhancement RRC Connection Enhancement -- R6R6UE RNC
RRC Connection Request
• UE capability indication- HS-DSCH
RRC Connection Setup
• H-RNTI, DL HS-PDSCH info
RRC Connection Complete
• (HS-DSCH physical layer category)
4-115
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
In R5, whenever a user is configured to use the HS-SCCH and HS-PDSCH, it is mandatory to set up
Dedicated Physical channels (DPCH) in both the UL and DL. The DPCH carries pilot and TPC bits
(control part) if the user is not doing any conversational services. Since each DPCH requires a code to be
used in UL and DL, R6 introduced the Fractional Dedicated Physical Channel (F-DPCH), a more efficient
management of code resources that allows HSDPA users to share given codes. To maximize the number
of UEs that can be multiplexed on one code, it is assumed that:
• DCCH signaling is carried on the HS-DSCH
• UE-specific TPC bits are present to maintain the UL power control loop for each UE
• Pilot bits can be present to allow the F-DPCH to be power-controlled and allow DL
synchronization to be maintained by each UE. However, further study is required to determine
whether the F-DPCH needs to carry dedicated pilots.
This slide illustrates the dedicated channels DPCH1, DPCH2 and DPCH3 associated with HS-SCCH(s)
and HS-PDSCH(s) for 2 different UEs configured to use HS-SCCH and HS-PDSCH.
When the DL timings of these channels are properly chosen, it appears that the DL spreading codes is not
necessary to distinguish between the UEs. A single code is sufficient to carry TPC and pilot bits associated
with these HSDPA UEs and still maintain the same periodicity of one slot for the transmission of this
information in the downlink.
If only TPC bits are transmitted, the number of TPC bits can be the same as in R99, or can be increased to
equal the number of pilot bits in R99.
F-DPCH Requirement
4-116
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Subframe SubframeSubframe#1#0
Subframe Subframe Subframe#3 #4 #5 #6 #7#2
FF--DPCH Requirement DPCH Requirement
UE1
UE2
Node B
CPICH
10 ms
PCCPCH
UE 1 DPCH
UE 2 DPCH
Subframe Subframe
UL 1 DPCCH
UL 2 DPCCH
TPC +Pilot bits for one slot
F-DPCH
HS-PDSCH
4-117
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The RNC receives the RANAP RAB Assignment Request message from the SGSN requesting RAB
assignment. The RNC requests a Node B to prepare for reconfiguration of the F-DPCH in the downlink.
The RNC sends a Radio Link Setup Request message. The Node B reserves necessary resources and
configures the new radio link(s) according to the F-DPCH information, such as DL power control,
included in the message. It also includes the reference F-DPCH transmission power in case the Node B is
configured to use the F-DPCH in the downlink. It ranges from 0 to 6 dB in steps of 0.25 dB.
The Node B responds to the RNC by sending an RL Setup Response message to RNC.
Once the RNC receives the F-DPCH parameters, it forwards them to the UE in a Radio Bearer Setup
message. The message includes the downlink F-DPCH information for each radio link. The information
consists of elements such as:
• Primary CPICH usage for channel estimation
• The F-DPCH frame offset is called τF-DPCH,n which contains offset (in number of chips) between the
beginning of the P-CCPCH frame and the beginning of the F-DPCH frame
• Secondary CPICH information
• Secondary scrambling codes
• Code numbers
• TPC combination index radio links with the same index have TPC bits, which for the UE are
known to be the same
F-DPCH Assignment
4-118
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
FF--DPCH AssignmentDPCH AssignmentUE Node B SGSN
RL Setup Request
RNC
RAB Assignment Request
RL Setup Response
Radio Bearer Setup
• RAB ID
• F-DPCH info • Power Offset info
• Downlink F-DPCH info for each RL
4-119
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
The UE transmits an ACK/NACK in response to HS-DSCH transmission. In R5, when the ACK/NACK
is not transmitted on the HS-DPCCH, the UE always uses DTX in the ACK/NACK field of the HS-
DPCCH. For example, if the UE fails to detect the HS-SCCH contents, the UE will use DTX in the
corresponding ACK/NACK field. This may lead the Node B to misinterpret this DTX as an ACK, which
might cause loss of the HS-DSCH data at the physical layer.
To reduce the probability of such misinterpretations, the transmission power of ACK messages must be set
to a high value. So, there should be a desirable method by which the Node B can set its ACK detection
threshold closer to DTX without resulting in misinterpretations. R6 employs an effective method to
distinguish between DTX and ACK on the HS-DPCCH without requiring large ACK transmit power.
Along with ACK/NACK transmit power, the Preamble (“PRE”) and Postamble (“POST”) are being
transmitted on HS-DPCCH. The code words of PRE and POST are given in the slide. The PRE codeword
is transmitted in a packet burst prior to transmitting the HARQ ACK message when the UE detects the
HS-SCCH control information. A POST codeword is transmitted after transmission of a HARQ ACK
message, unless another HS-DSCH packet is detected. The transmission of the PRE and POST codeword
depend on the current value of repetition factor N_acknack_transmit and the UE capability inter-TTI.
ACK/NACK Transmit Power Reduction - R6
4-120
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
ACK/NACK Transmit PowerACK/NACK Transmit PowerReduction Reduction -- R6R6
Node BUE
ACK ACK
NACK NACK
PRE PRE
POSTPOST
1111111111
0010010010
0000000000
0100100100
Channel Coding
(1, 10)
# of I/P bits
# of O/P bits
HS-DPCCH info
4-121
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
This example shows how preamble (PRE) and postamble (POST) code words are sent when
N_acknack_transmit = 1. For clarity, the HS-DPCCH and HS-SCCH subframes corresponding to the HS-
DSCH subframe “N” are both given the same subframe designation, “N.” The two parts of this scheme are
as follows:
• The UE transmits a PRE in subframe N-1 on the HS-DPCCH when the UE detects control
information for it in subframe N on the HS-SCCH. The preamble is not transmitted in subframe N-
1 if an ACK or NACK is to be transmitted in N-1 as a result of a packet in an earlier subframe on
the HS-DSCH
• The UE decodes the HS-DSCH packet and transmits the HARQ ACK/NACK in subframe N on the
HS-DPCCH. If the UE's Inter TTI capability is 1, the UE transmits a POST in subframe N+1 on
the HS-DPCCH (unless a packet is detected in subframe N+1 on the HS-DSCH, in which case an
ACK/NACK is sent, or HS-SCCH control information is detected in subframe N+2, in which case
a PRE is sent).
If the UE's inter-TTI capability is greater than 1, there is no need to transmit the POST in subframe N+1,
because an HS-DSCH packet cannot be received in subframe N+1 on the HS-DSCH.
From subframes N+2 and onward on the HS-DPCCH, the UE goes back to using the DTX in the
ACK/NACK field unless new relevant control information is detected on the HS-SCCH.
Pre - Post Example
4-122
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Pre Pre -- Post ExamplePost Example
N N+2 N+3N+1
N N+1 N+2 N+3Data packet
HS-SCCH
HS-DSCH
HS-DPCCH PRE ACK or NACK POST
NN-1 N+1 N+2
PREAMBLE transmitted in sub-frame N-1 to indicate reception of relevant signaling information in sub frame N on HS-SCCH
Normal ACK/NACK to indicate correct or incorrect decoding of packet
POSTAMBLE transmitted in sub-frame N+1 (unless a packet is correctly decoded from sub-frame N+1 on the HS-DSCH, or control information is detected in sub- frame N+2 on the HS-SCCH
4-123
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Summary
4-124
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
SummarySummary• RRC establishment procedures have been
enhanced to include the HS-DSCH capability of the UE
• Radio Link (NBAP), Radio Bearer Setup (RRC) and Radio Bearer reconfiguration procedures have been enhanced to assign HSDPA logical, transport and physical channel parameters to the UE
• The SRNC configures the Node B and UE with QoS parameters for receiving scheduled data at the UE and the scheduling of resources at the Node B
• The UE determines the CQI and reports it on the HS-DPCCH. The Node B uses this as one of the key inputs to schedule HS-DSCH resources.
• When an HS_DSCH best cell change occurs, intra-Node B and inter-Node B handovers are possible
4-125
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Review Questions
4-126
Mastering HSDPA/HSUPA Signaling
HSDPA Data Call Setup
Review QuestionsReview Questions1. Which message carries HS-DSCH physical
layer capabilities?2. What is the significance of assigning an
H-RNTI?3. What is a MAC-d flow?4. What is the purpose of the queue ID and
TSN in the MAC-hs header?5. What is the function of the HARQ entity in
the UE and Node B?
4-127
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
HSUPA Data Call HSUPA Data Call SetupSetup
5-1
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Objectives
5-2
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
ObjectivesObjectives
After completing this module, you will be able to:• Identify the RRC Connection enhancements• Describe the Radio Bearer enhancements during
HSUPA data call set up• List the HSUPA channel assignments• Describe how the UE selects the E-TFC and how the
Node B schedules during an HSUPA data call• List the various types of radio reconfiguration types
used during HSUPA data call set up• List various types of handovers used in HSUPA and
when they are used
5-3
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The support of HSUPA requires enhancement of the Radio Resource Control (RRC), Message
Authentication Code (MAC) and physical layer protocols.
Some of the Major RRC enhancement procedures required are mentioned below for HSUPA Release 6
implementation:
• RRC connection establishment needs enhancement to support HSUPA capabilities at the UE and
assignment of signaling radio bearers for the control plane
• HSUPA introduces a new HSUPA Enhanced Dedicated Channel (E-DCH) transport channel, and
uplink and downlink physical channels. The RRC is responsible for assignment of E-DCH transport
channel parameters, physical channel spreading codes and their spreading factors.
• Radio bearer setup and radio bearer reconfiguration have been enhanced to configure logical
channels, E-DCH transport channels and physical channels according to Quality of Service (QoS)
requested by the core network
• The RRC at the Radio Network Controller (RNC) configures the RRC at the UE with certain QoS
parameters that enable the UE to choose the best transport block size and enhanced transport format
combination selection (E-TFC selection) for high speed uplink data transmission.
• The RRC decides, coordinates, and executes soft handovers during HSUPA calls. This can be
within sectors of the serving Node B or Inter Node B/Inter RNC.
HSUPA Enhancements
5-4
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
HSUPA EnhancementsHSUPA Enhancements
RRC Enhancements
E-TFC selection Handover Procedures
(Best Cell Change)
GrantsInterference management
HARQ+IR
UE-RRCRNC-RRC
MAC-e RL Setup changes
Radio Bearer Enhancements
MAC-es
Node B
5-5
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The MAC layer is also enhanced at both the UE and UMTS Terrestrial Radio Access Network (UTRAN)
to support high speed uplink transmission.
A new MAC entity (MAC-es) is added at the Serving Radio Network Controller (SRNC) to provide in-
sequence delivery (re-ordering) and to handle combining of data from different Node Bs in a soft
handover.
A new MAC entity (MAC-e) is introduced in the Node B to handle HARQ retransmissions, scheduling
and MAC-e demultiplexing.
A new MAC entity (MAC-es / MAC-e) is implemented in the UE below the MAC-d. The MAC- es /
MAC-e in the UE handles Hybrid ARQ (HARQ) retransmissions, scheduling, MAC-e multiplexing, and
transport block size selection (Enhanced Dedicated Channel (E-DCH) Transport Format Combination (E-
TFC) selection).
HSUPA Enhancements (continued)
5-6
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
HSUPA Enhancements HSUPA Enhancements (continued)(continued)
RRC Enhancements
E-TFC selection Handover Procedures
(Best Cell Change)
GrantsInterference management
HARQ+IR
UE-RRCRNC-RRC
MAC-e RL Setup changes
Radio Bearer Enhancements
MAC-es
Node B
5-7
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
To perform cell re-selection, the UE first needs to know the necessary system information about the
system it is camping on. In addition, the UE needs to be aware of the systems that are in the surrounding
geographical area – the neighbor cells.
The UE searches for the strongest cell and performs the Public Land Mobile Network (PLMN) selection
and cell selection. First, it synchronizes with the current cell. Then it monitors the Broadcast Channel
(BCH) and gathers information about the current cell and its neighbors from the System Information
Blocks (SIBs). The system information block groups together system information of the same nature. The
SIBs are sent on the BCH periodically. The UMTS specification describes over fifteen different types of
SIBs. The SIBs that carry information relevant for cell selection and re-selection are SIBs 1, 2, 3, 4, 5, 11
and 12.
For example, SIB 1 carries various parameters related to Non Access Stratum (NAS) and the core
networks (CN). It also specifies various constants and timers the UE has to use during various operations
such as cell re-selection. Various cell selection and re-selection criteria are specified in SIB 3 (for idle
mode) and SIB 4 (for connected mode). In addition, SIBs 11 and 12 also describe parameters related to
specific radio measurements. The system information block type 5 contains parameters for the
configuration of the common physical channels in the cell.
In Release 6, SIB 5 has been modified to indicate whether there is an HSUPA-capable cell, which means
that the UE may consider this cell as part of the HSUPA coverage area.
The UTRAN broadcasts the “EDCH cell indicator” in SIB block 5 to indicate whether the cell is HSUPA-
capable. Please Refer to 25.331 specs for further details.
HSUPA Cell Indicator
5-8
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
HSUPA Cell Indicator HSUPA Cell Indicator
R6 Indicates HSUPA-capable Cell
SIB 5 Configuration of Common
Physical Channel ParametersEDCH Cell Indicator
5-9
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The figure depicts an overview of the procedures involved in the data call setup scenario. The first
mandatory procedure is to set up resources for the control plane. Therefore, the scenario starts with the
“Radio Resource Control (RRC) Connection Establishment” to create the UE – UMTS Terrestrial Radio
Access Network (UTRAN) signaling connection. Once the RRC connection has been established, the UE
contacts the core network using the first Non Access Stratum (NAS) message (here called Service
Request). As usual, the core network may or may not initiate the security procedures like authentication.
Assuming that the outcome has been successful, the UE starts the “Log in” procedure, which also is a
request for an IP address. This procedure is called “Packet Data Protocol (PDP) Context Activation,”
which also involves the negotiation of the QoS parameters.
After a successful negotiation, the Serving GPRS Support Node (SGSN) triggers the setup of resources for
the user plane using the Radio Access Bearer (RAB) Assignment procedure. Here we assume, based on
the QoS parameters, that the Radio Network Controller (RNC) always sets the cell Dedicated Channel
(DCH) to be the RRC state for the UE to establish the HSUPA radio bearer. Therefore, it starts the Radio
Link Setup procedure toward the Node B on the Iub interface. Once the RNC and the Node B have further
synchronized the bearer, the RNC can start the Radio Bearer Setup procedure over the air interface. The
PDP context procedure is finalized with an Accept message sent by the SGSN to the UE.
Data Call Setup - HSUPA
5-10
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Data Call Setup Data Call Setup -- HSUPAHSUPAUE RNC GGSN
1. RRC Connection Establishment
2. Service Request
3. Security Procedures
4. PDP Context Activation Request
6. RL Setup5. RAB Assignment
8. Act. PDP Context Accept
7. Radio Bearer Setup
Node B SGSN
Bearer Synch
5-11
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
In addition to “R99” and “R5” parameters, the RRC connection establishment procedure in “R6” carries
some important parameters that indicate Enhanced Dedicated Channel (E-DCH) support. The major
parameters transmitted include:
1. The RRC Connection request sent by the UE
• Initial identity: PTMSI, TMSI and RAI (Routing Area Identity).
• Establishment Cause: Originating streaming call, originating interactive call, originating
background call, etc.
• Domain Indicator: Indicates whether the CN (Core Network) is circuit-switched (CS) or
packet-switched (PS). In the case of an HSUPA data call, the call is routed by the RNC to
the SGSN in the PS domain through the Iu Interface.
• The Access Stratum release indicator should support “R6” also
• The UE sends a UE-capability indication that it is capable of supporting E-DCH( HSUPA)
+ HS-DSCH (HSDPA) functionality or only HS-DSCH functionality
RRC Connection Enhancements
5-12
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
RRC Connection EnhancementsRRC Connection EnhancementsUE RNC
RRC Connection Request
• UE Capability Indication - HS-DSCH+E-DCH
RRC Connection Setup
• Primary E-RNTI, Secondary E-RNTI, E-DCH info
RRC Connection setup Complete
• EDCH Physical layer category
5-13
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
2. Radio Resource Control (RRC) connection setup is sent by the UMTS Terrestrial Radio
Access Network (UTRAN)
• Enhanced Dedicated Channel (E-DCH) Radio Network Temporary Identifier (E-
RNTI) Assignment: The E-RNTI is the HSUPA UE Identity. The E-RNTI indicates that
the UE has a High Speed Physical Downlink Shared Channel (E-DCH) assignment within
a cell. There are two types of E-RNTIs: Primary E-RNTI and secondary E-RNTI. A UE
can be assigned both a primary and secondary E-RNTI or only a secondary E-RNTI. All
UEs can be assigned only primary E-RNTIs. If the UE needs to be given another set of
resources based on the Quality of Service (QoS), it can be assigned a separate secondary E-
RNTI. The E-RNTI variable is a 16-bit string and stores the assigned E-RNTI for this UE
when in CELL-DCH state and an Enhanced Dedicated Channel (E-DCH) transport channel
has been allocated.
• E-DCH Information: E-DCH information includes parameters such as Enhanced
Dedicated Physical Control Channel (E-DPCCH) information, Enhanced Dedicated
Physical Data Channel (E-DPDCH) information, and whether the radio link is a serving
link. It also includes the E-DCH Absolute Grant Channel (E-AGCH), E-DCH Relative
Grant Channel (E-RGCH) and E-DCH HARQ Acknowledgement Indicator Channel (E-
HICH) spreading codes for each link. This message also indicates whether UE radio access
capability is required to be sent on the Radio Resource Control (RRC) Connection
Complete message.
RRC Connection Enhancements (continued)
5-14
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
RRC Connection Enhancements RRC Connection Enhancements (continued)(continued)
UE RNC
RRC Connection Request
• UE capability Indication - HS-DSCH+E-DCH
RRC Connection Setup
• Primary E-RNTI, Secondary E-RNTI, E-DCH info
RRC Connection Setup Complete
• EDCH Physical layer category
5-15
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
3. Radio Resource Control (RRC) Connection Setup Complete
• The UE now enters the “CELL-DCH” state and sends the last RRC message for the
establishment of the RRC connection called “RRC Connection Setup Complete.” It sends
the CN domain ID and, if asked in the RRC Connection Setup, its Radio Access
Capability. This message is sent using the RLC-AM, and the RNC responds with an “RLC
Status PDU” (an acknowledgement) to handshake the start of the acknowledge mode with
the UE. The UE sends the Radio access capability, which contains the most information for
the Enhanced Dedicated Channel (E-DCH).
• Physical Channel Capability: This indicates the support of the E-DCH and the physical
layer category (UE categories 1-6). Each UE category indicates the maximum number of
E-DCH codes transmitted, minimum spreading factor, support of the 10 ms and 2 ms
Transmission Time Interval (TTI) E-DCH, and the maximum number of bits of an E-DCH
transport block transmitted within 10 ms and 2 ms E-DCH TTI.
RRC Connection Enhancements (continued)
5-16
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
UE RNC
RRC Connection Request
• UE capability Indication - HS-DSCH+E-DCH
RRC Connection Setup
• Primary E-RNTI, Secondary E-RNTI, E-DCH info
RRC Connection setup Complete
• EDCH Physical layer category
RRC Connection Enhancements RRC Connection Enhancements (continued)(continued)
5-17
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Service Request: The service request is defined as the Initial Direct Transfer message in UMTS. It is sent
to the RNC by the UE containing the UE identity in the Packet-Switched (PS) domain (P-TMSI), a
reference number to the latest authentication procedure, Key Set Identifier (KSI) and the type of service
(Signaling).
On receiving the initial Direct Transfer (service Request) from the UE, the RNC further transfers the
request to the SGSN using a Connection Oriented message to set up the Iu connection.
In response, the SGSN starts security procedures, which includes the Security Mode Command. This
message carries the specified ciphering and integrity protection algorithm and keys to be used by the
UTRAN. Once the security procedures are completed, all subsequent signaling and data are sent securely
over the air interface.
When all the bearer channels are set up for carrying traffic, the UE sends an SM Activate PDP Context
Request for the SGSN. It is an RRC Direct Transfer message, which is sent over the Iu interface by the
RANAP Direct Transfer. The purpose of the message is to describe the service that the UE wants to
activate, and contains the requested QoS profile. The message includes the NSAPI, and is added to
identify this PDP context. To communicate with the packet-switched (PS) domain, it is essential to have
information regarding the IP address. It also includes the “Requested PDP Address” parameter and Access
Point Name (APN), which determines the entity that allocates the IP address. It also includes the Logical
Link Control Service Access Point Identifier (LLC- SAPI).
The SGSN now receives the Activate PDP Context message from the RNC using the RANAP DT over the
Iu connection. Once it receives the request, it first uses the APN to find the GGSN and then starts a
“handshake” with the GGSN to negotiate the QoS parameters and create the GTP tunnel.
In response, the GGSN then sends a “Create PDP CTX Request” to the RNC, which indicates that the CN
has provided the mobile with resources needed for packet transfer, and includes the negotiated QoS profile
with the UE IP address. Once the GTP tunnel is created, the tunnel endpoint identity TEIDS and GGSN IP
address are also sent.
As compared to R99, no changes are required in the service request to support HSUPA. The only
difference is that higher QoS can be supported.
Initial Data Call Setup
5-18
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Initial Data Call SetupInitial Data Call SetupUE RNC GGSNInit. Dir. Transfer (Service Req.)
CR [IUM (Service Req.)]
UL DT (Activate PDP CTX Req.)
DT (Act. PDP CTX Req.)
SGSN
Create PDP CTX Req.
Security Procedures
Create PDP CTX Resp.
Check subscription: APN & QoS
use APN GGSN addr
• No Changes for HSUPA except that higher QoS canbe requested/negotiated
Requested QoS Profile• Traffic Class: Interactive• Max Bitrate
• P-TMSI• Service Type: signaling
5-19
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The RAB Assignment Request is sent by the CN to the RNC, which includes the RAB ID and QoS. This
indicates a need for relatively high bit rates on uplink. Some additional inquiry regarding UE capability is
required in Release 6 to support HSUPA
If the UE Capability was not received during the Radio Resource Control (RRC) Connection Complete
message, the UTRAN asks for the mobile capability using the UE Capability Inquiry message. The most
interesting information element here, for the RNC, is the so-called “UE Physical layer Category.”
Since the RNC has requested a capability update, the UE sends the UE Capability Information message.
The most valuable piece of information here is whether the UE supports the Enhanced Dedicated Channel
(E-DCH) (HSUPA) and, if so, its category. These parameters are included in the Physical Channel
Capability message.
UE Capability - R6
5-20
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
UE Capability UE Capability -- R6R6
Node B
UE
RNC
UE Capability Inquiry
CN
RAB Assignmt Req
UE Capability Information Only if not sent in RRC
Connection Establishment
(Request for RA – Capability including category info)
• DL Capability with simultaneous HS-DSCH configuration
• PH-CH Capability• Support for E-DCH• E-DCH “Category”
5-21
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
When the service between the GGSN and SGSN is negotiated with a specific QoS profile, the SGSN sends
a RANAP RAB Assignment Request message to the RNC to set up user plane resources. Then, it requests
the UTRAN to allocate the necessary radio resources via the Radio Access Bearer (RAB) Assignment
Request.
The RAB assignment is the mechanism for the CN to notify the UTRAN of the appropriate Quality of
Service (QoS) and attributes required to delivery of the service. This request is translated into a radio link
setup request sent from the Radio Network Controller (RNC) to the Node B via Node B Application Part
(NBAP) signaling. It is also translated into a Radio Bearer Setup message sent from the RNC to the User
Equipment (UE) via Radio Resource Control (RRC) signaling. Once the radio resources have been
assigned and set up, the RNC communicates with the Node B with the AAL2 bearer. The RAB
Assignment Response completes the RAB by setting up the Iu (GTP) between the SGSN and RNC in the
case of a packet-switched data call. An ATM Adaptation Layer Type 5 (AAL5) connection is set up
between the RNC and Node B.
Finally, the resources available at the Node B and UE agree to the radio bearer, and a successful RAB
assignment response is sent to the Packet Switched Core Network (PS-CN).
Radio Access Bearer Assignment
5-22
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
UserPlane
Radio Access Bearer AssignmentRadio Access Bearer Assignment
RNCNode B
PS-CN PSTNIub IuUu
IuRRC
Setup Radio Link
AAL2 BearerPhysical Channel
Setup Radio Bearer
Iu/AAL5
Complete the RAB
Radio Bearer (RB)
UE
RAB RB+Iu (GTP) bearer defines required QoS
ControlPlane
5-23
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Let us discuss basic terminology introduced as part of Enhanced Dedicated Channel (E-DCH) operations
in HSUPA. The E-DCH is independent of the DCH defined in R99. Radio resource allocation and
configuration does not have to be identical to R99-based DCH allocations or R5-based HS-DSCH
allocations.
• DCH Active Set: R99-defined active set. The set of cells that provides radio resources to carry
traffic for the DCH. Per the R99 definition, it is a collection of cells that support DCH traffic to the
UE in both uplink and downlink directions.
R6 defines the E-DCH active set, serving E-DCH cell, serving E-DCH Radio Link Set and non-serving E-
DCH radio links for HSUPA operations. Let us define these terms now.
• E-DCH Active set: It defines the set of cells that carry the traffic for E-DCH on the uplink. These
cells also support associated physical layer channels on the downlink to support E-DCH operations
for the UE. The E-DCH active set is an identical or a proper subset of the DCH active set.
• Serving E-DCH cell: This is the cell from which the UE receives absolute grants for E-DCH. In
other words, this cell controls the radio resource allocations (i.e., power offset with respect to
DPCCH for the E-DPDCH). Each UE on the E-DCH has one and only one serving cell. The
serving E-DCH cell is a member of the serving E-DCH RLS.
• Serving E-DCH Radio Link Set (RLS): This is defined as the set of cells, including the serving
E-DCH cell, from which the UE may receive and combine relative grants. From a practical
perspective, the serving E-DCH RLS consists of the active set member cells from the Node B that
contains the E-DCH serving cell.
• Non-serving E-DCH RL: Every cell that belongs to the E-DCH active set but is not part of the
same Node B that contains the serving cell. These cells send relative grants to the UE, but these
grants cannot be combined at the UE receiver. Every UE on E-DCH may have zero, one or more
non-serving E-DCH radio links.
E-DCH Terminology
5-24
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DCH TerminologyDCH Terminology
C3 C1
C2
Node B1 Node B2
Node B3
C5
C4DCH Active Set: {C1, C2, C4, C5}
E-DCH Active Set:{C1, C2, C4}
C1: E-DCH Serving Cell
Serving E-DCH RLS:{C1, C2}
Non-serving E-DCH RLS: {C4}
5-25
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This diagram illustrates the role of different channels involved in HSUPA. In this example, the Enhanced
Dedicated Channel (E-DCH) has an active set consisting of 3 sectors from 2 different Node Bs. A serving
E-DCH cell is designated by the RNC as part of radio link setup process through Radio Resource Control
(RRC) signaling. The cells that are not part of the serving cell’s Node B are referred to as the non-serving
E-DCH radio link set. The following channels are processed by the UE:
1. The UE receives absolute grant information from the E-DCH serving cell on the E-DCH Absolute
Grant Channel (E-AGCH).
2. The UE also receives a relative grant (i.e., corrections) from the serving and non-serving E-DCH
RLSs on the E-DCH Relative Grant Channel (E-RGCH).
3. The UE transmits information on the uplink using the E-DPDCH (and associated control
information is sent on the E-DPCCH).
4. When the E-DCH Active Set cells receive this information, a Hybrid ARQ (HARQ) process at
each cell (in the E-DCH Active Set) transmits an ACK or a NACK based on the information
received related to current packets using the HARQ approach.
5. Along with HSUPA channels, R99 channels, DL DPCH and UL DPCH also exist. These
channels consist of pilot and power control bits. The power control bits sent on the DL DPCH are
used to power control UL DPCCH. E-DPDCH and E-DPCCH powers are relative to the UL
DPCCH power.
Channel Usage
5-26
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Channel UsageChannel Usage
UE
Serving Node B
High Speed Data and control data
E-DPDCH / E-DPCCH
Scheduling/Noise Control
E-AGCH/E-RGCH
Scheduling
E-DPDCH / E-DPCCH
E-RGCH
E-HICHE-HICH
ACK/NACK
Data, Signaling / TPC, TFCI, Pilot
DPDCH/DPCCH
DPCH
Data, Signaling / TPC, TFCI, Pilot
DPCH
DPDCH/DPCCH
Noise Control
Non-Serving Node B
5-27
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
HSUPA physical downlink channel information is sent on the Radio Bearer Setup or Radio Bearer
Reconfiguration message.
• E-AGCH spreading codes of spreading factor 256 are carried by the Radio Bearer Setup message
or Radio Bearer Reconfiguration message from the RNC to the UE.
• The RNC assigns E-RGCH spreading codes of spreading factor 128 to the UE and also sends one
of the 40 signature sequences for each radio link on the serving and non-serving RLS. The relative
grants are primarily power control commands chosen according to the uplink RoT measured by the
serving and non-serving RLSs.
• The RNC also assigns E-HICH information to the UE for every radio link in the serving and non
serving RLSs whose spreading codes and signature sequences are the same as the E- RGCH. The
E-HICH carries HARQ ACK/NACK information.
HSUPA DL Channels Assignment
5-28
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
HSUPA DL Channels AssignmentHSUPA DL Channels Assignment
Node B
Node B
Serving RLS
Non-Serving RLS
UE
E-AGCH
• E-AGCH CC with SF = 256• Only assigned by serving E-DCH
cell
E-RGCH
• E-RGCH CC with SF = 128 and signature sequences
• Serving and non-serving RLS
HICH
• Same CC and signature seq. asE-RGCH
• Serving and non-serving RLS
RB setup
5-29
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The E-DCH Dedicated Physical Data Channel (E-DPDCH) carries the E-DCH transport channel. The E-
DPDCH supports both 10 ms TTI and 2 ms TTI. If 2 ms TTI is used, E-DPDCH uses a 2 ms subframe for
transmission. Depending on the data rates required for uplink E-DCH transmission, the UE may use 1 or
more E-DPDCHs. The E-DPDCH uses a range of spreading factors (2 to 256) to support different data
rates. For example, to support a 1.92 Mbps data rate, the E-DPDCH uses SF = 2. As the data rates go
down, the SF value goes up (i.e., more spreading gain). For example, when the desired data rate on the E-
DPDCH is 60 kbps, SF = 64 is used. The E-DPDCH is power-controlled by the Node B. In addition, soft
handover is supported on the E-DCH. To support soft handover, HSUPA defines the concepts of serving
E-DCH cell, serving E-DCH Radio Link Set (RLS) and non-serving E-DCH RLS.
The E-DCH Dedicated Physical Control Channel (E-DPCCH) is the E-DCH associated physical layer
signaling channel transmitted by the UE. There is at most one E-DPCCH per UE. No E-DCH/E-DPDCH
transmission can occur without an associated E-DPCCH transmission. E-DPCCH control information is
transmitted at a rate of 15 kbps using a spreading factor of 256. The spreading code of E-DPCCH is fixed
to (CC256,1).
HSUPA UL Channel Assignment
5-30
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
HSUPA UL Channel AssignmentHSUPA UL Channel Assignment
UE Serving Node B
High Speed Data and Signaling
E-DPDCH / E-DPCCH
SchedulingNoise control
E-DPDCH / E-DPCCH
Non-Serving Node B
• Assigned in Radio Bearer Setup message• E-DPDCH CC SF varies from 2 to 256 • E-DPDCH sent on 2 or 10ms TTI• E-DPCCH CC is fixed (CC256,1)
5-31
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The SRNC configures the Node B and UE with various Quality of Service (QoS) related information.
Let us discuss the parameters provided by the SRNC to the Node B to enable reservation of resources and
scheduling.
• Scheduling priority for each logical channel mapped to the E- DCH and the corresponding mapping
between the logical channel identifier and DDI value.
– The Data Description Indicator (DDI) is nothing but mapping between the MAC-d PDU
size and the Enhanced Dedicated Channel (E-DCH) MAC-d flow ID.
– The E-DCH MAC-d flows are defined as MAC-es PDUs, carrying MAC-d data sharing
the same traffic characteristics, and that can be multiplexed with MAC-es PDUs of the
same or other MAC-d flows on the MAC-e.
– There can be up to 8 MAC-d flows and 15 Logical channels that can be multiplexed on
the transport channel (E DCH).
• The maximum UL, UE power, non-scheduled grant for MAC-d flows
• The HARQ profile per MAC-d flow, which consists of the power offset attribute and maximum
number of transmissions attribute
• E-DPCCH power offset: The Node B can use this power offset to convert between rate and power
in its resource allocation operation
• Power offsets for reference E-TFCs
Assignment of QoS Parameters to the Node B
5-32
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Assignment of QoS Parameters to the Assignment of QoS Parameters to the Node BNode B
Node BRNC
RLC AM/UM
RRC
DTCH 1 DTCH 2 DCCH
MAC-d
MAC-d flows
MAC-es
MAC-d flows
MAC-d flow =1
MAC-d flow =2
MAC-e
Logical Channel IDsLogical Cha PriorityMAC-d Flow IDs
RL Setup Request
DDI• E-DCH MAC-d Flow ID • MAC-d PDU size • MAX UE Power
• E-DPCCH PO
HARQ• Power Offset• Max # of
Transmissions
5-33
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The QoS related parameters provided by the SRNC to the UE on the Radio Bearer Setup message enable
QoS-based E-TFC selection. The MAC-e functionality at the UE performs E-TFC selection, the
multiplexing of logical channels in MAC-e PDUs and HARQ operation.
E-TFC selection Parameters
• Power Offset for Reference E-TFCs: The reference E-TFC and its power offset are sent to
the UE, mainly to maintain the same level of quality for other E-TFCs calculated by UE
identical to reference E-TFCs
• E-DPCCH Power Offset: This is the relative power difference between the DPCCH and E-
DPCCH
DDI (Data Description Indicator)
• Logical Channel Priority: The priority is based on the QoS requested by the UE. For
example, logical channel DTCH 1 can have a high priority than DTCH 2.
• Mapping between Logical Channels and MAC-d Flows: For example, DTCH 1 is mapped
to MAC-d flow ID 1. DTCH 2 and DCCH are multiplexed as a single MAC-d flow ID 2.
HARQ Profile
• The HARQ Profile per MAC-d flow consists of the power offset attribute and maximum
number of transmissions attribute. The E-TFC selection mechanism in the UE uses the power
offset attribute to choose the BLER operating point for the transmission. Maximal latency can
be regulated by the maximum number of transmissions attribute.
Grant Parameters
• Non-Scheduled grant for MAC-d flows configured for non-scheduled transmissions
Assignment of QoS Parameters to the UE
5-34
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Assignment of QoS Parameters Assignment of QoS Parameters to the UEto the UE
UE Node B RNC
RRC
MAC-es / e
DTCH 1 DTCH 2
RLC AM/UM
RRC Radio Bearer Setup• DDI Logical channel id, PDU size. MAC-d flow ID• E-TFCI selection Parameters, Happy bit delay condition
MAC- d flowsMAC-d flow 1
MAC-d flow 2
DDI E-TFC Selection Parameters
HARQ Profile
Non-Scheduled Grant
DCCH
MAC-d
5-35
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Up to this point, the RNC has been informed, from the SGSN, about the requested QoS parameters, and
has also found out exactly what the UE may be able to support. Therefore, it is now time to start preparing
the Node B for traffic. For that reason, the RNC sends the radio link setup request over the Iub interface
using the Node B Application Part (NBAP) protocol. This message contains all the parameters it had for
R99 and R5, but now has the HSUPA-related parameters as well. Some important parameters are:
• Enhanced Dedicated Channel (E-DCH) RL Indication: Indicates whether each link in the active
radio link set is an E-DCH RL
• E-AGCH, E-RGCH and E- HICH power offset
• Maximum number of spreading codes for the E-DPDCH and the puncture limit. The puncture limit
indicates the amount of puncturing applied in order to minimize the number of dedicated physical
channels.
• Reference E-TFCI information and the reference E-TFCI power offset
• The 2 ms or 10 ms TTI information for the E-DCH, which indicates whether the RSN-based RV
index is used or RV = 0
• The list of E-DCH MAC-d flow IDs and their corresponding power offsets, and the maximum
number of transmissions
• Scheduling priority indicator, E-DCH DDI value mapping with MAC-d flow ID and MAC-d PDU
size, as well as the maximum number of bits per MAC-e PDU
RL Setup Enhancements
5-36
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
RL Setup EnhancementsRL Setup EnhancementsUE Node B SGSN
RL Setup Request
RNC
RAB Assignment Request
RL Setup Response
• E-DCH DDI mapping • Maximum number of EDPDCH CCs
5-37
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Upon reception of the RL Setup Request message, the Node B is supposed to answer with the Radio Link
Setup Response message. Again, on top of all Release 99- and R5-related parameters, we also see the
HSUPA-related parameters, such as:
• The spreading code of E-AGCH, E-RGCH and E-HICH for each radio link
• The signature sequences of the E_RGCH and E-HICH for each radio link
• Primary E-RNTI and secondary E-RNTI value and an indication whether the Grant selector is
primary or secondary
• Serving cell determination of the initial serving grant value
• HARQ process allocation for scheduled transmission grant and 2 ms non–scheduled grant
RL Setup Enhancements (continued)
5-38
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
RL Setup Enhancements RL Setup Enhancements (continued)(continued)
• Pri E-RNTI, Sec E-RNTI• E-AGCH, E-RGCH, E-HICH CC
UE Node B SGSN
RL Setup Request
RNC
RAB Assignment Request
RL Setup Response
5-39
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
After negotiating and setting up resources on the Iub interface, the RNC sends the Radio Bearer Setup
message to the UE. The Radio Bearer Setup message contains:
• E-AGCH, E-RGCH and E-HICH spreading codes and their signature sequences, primary E-RNTI,
secondary E-RNTI and primary or secondary E-RNTI grant selector
• The E-DPCCH power offset, which is the E-DPCCH/DPCCH power offset and
Happy_Bit_Delay_Condition. The happy bit delay condition is the time over the current grants
relative to the TEBS (Total E-DCH buffer status) is evaluated. This is done after the E-TFC
selection procedure.
• The E- TFC selection parameters such as the list of reference E-TFC and its power offset
• Mapping between the logical channel, MAC-d PDU size, MAC-d flow ID and Data Description
Indicator (DDI). For each MAC-d flow, its power offset and maximum number of transmissions
and also the list of options of various E-DCH MAC-d flows that can be multiplexed into one MAC-
e PDU.
• HARQ indication whether it is RV=0 or an RSN-based RV index
• Maximum number of E-DPDCH spreading codes (2 to 64) and puncturing limit
• Initial serving grant and non-scheduled grant
• E-DCH scheduling Information parameters
• The UE acknowledges reception of the Radio Bearer Setup message by sending the Radio Bearer
Setup Complete message. On the Iu interface, using the RANAP protocol, the RNC now sends the
RAB Assignment Response to notify the SGSN that all the resources within the UTRAN have been
granted for the requested QoS.
The SGSN, having made sure that the requirements for the QoS are met, addresses the Activate PDP
Context Accept message to the UE. In this message, the SGSN informs the UE (in addition to all other
mandatory parameters) of the final negotiated set for the QoS.
RAB Setup Enhancements
5-40
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
RAB Setup Enhancements RAB Setup Enhancements UE Node B SGSNRNC
RAB Assignment Request
Radio Bearer Setup
Radio Bearer Setup CompleteRAB Assignment Response
DL DT (Act PDP CTX Accept)DT (Activate PDP CTX Accept)
• DDI mapping, E-RNTI, maximum number of EDPDCH CCs
• HARQ info. E-FC selection parameters
• RAB ID
• The final negotiated QoS
5-41
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This diagram captures the complete set of R6 channels. To operate HSDPA and HSUPA, R99 channels are
still required for pilot reference and power control. In addition, there can be a scenario of Multi RAB calls
in which a UE can be on an R99 voice call with HSDPA download and HSUPA upload. This also requires
presence of R99 channels in addition to HSDPA and HSUPA channels. In this example, the UE is in soft
handover with C11, C21 and C10 Node Bs. C10 is the serving Node B for both HSDPA and HSUPA. C11
and C12 are Node Bs consisting of non-serving RLSs for HSUPA operation. If the UE is on an R99 voice
call, it is served by all 3 Node Bs.
R99 channels include:
• DL DPCH: Carries voice, signaling, pilot, power control commands (TPC) and TFCI (Transport
Format Combination Identifier), if the R99 voice call exists. Otherwise, it carries signaling, pilot,
and power control commands if only an HSDPA or an HSUPA call exists.
• UL DPCH- DPDCH+DPCCH: The DPDCH channel carries voice and signaling with its
associated channel DPCCH carrying pilot, TFCI and TPC.
For HSDPA operation:
• The downlink uses the High Speed Common Control Channel (HSCCH). The HSCCH carries the
Channelization Code Set (CCS), Modulation Type (M), Transport Block Size (TBS), HARQ
Process Identifier(HAP), Redundancy Version (RV), New Data Indicator (NDI) and H-RNTI
masked with CRC. This information enables the UE to understand HS-PDSCH assignment
parameters. Using this information, the UE can receive and decode the scheduled data sent on the
HS-PDSCH, transmitted in the next 2 ms TTI. When on an HSDPA call, the UE can be served by
one and only one serving Node B. For example, C10 is the serving Node B that supports HSDPA
functionality. No soft handover in downlink is possible, whereas soft handover in the uplink can
still exist.
• On the uplink, the UE transmits the High Speed Dedicated Physical Control Channel (HS-
DPCCH), which contains the Channel Quality Indicator (CQI) and ACK / NACK.
Complete R6 Channels
5-42
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Complete R6 ChannelsComplete R6 Channels
UE
C10High Speed Data and Signaling
E-DPDCH / E-DPCCH
Scheduling/Noise Control
E-AGCH/E-RGCH
Scheduling
E-RGCH
E-DPDCH / E-DPCCH
E-RGCH
E-HICH
E-HICH
E-HICHACK/NACK
E-DPDCH / E-DPCCH
DPDCH/DPCCHDPCH
DPDCH/DPCCH
DPCH
Voice, Data, Signaling / TPC, TFCI, Pilot
DPDCH/DPCCH
Voice, Signaling, TFCI, Pilot, TPC
DPCH
CQI, ACK/NACK
HS-DPCCH
High speed Control/Data
HS-SCCH/ HS-PDSCH
C11
C21
5-43
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
For HSUPA upload from the UE, C10 is the serving Node B that contains the Enhanced Dedicated
Channel (E-DCH) serving cell and other cells that are part of the serving RLS. C11 and C21 are non-
serving Node Bs, and all the cells in this Node B are part of E-DCH non-serving RLS. All cells in C10,
C11 and C21 are part of the E-DCH active set.
Downlink Channels are:
• E- AGCH: This is transmitted only by the serving cell and provides a scheduled grant to the UE
when the UE sends the scheduling request to the Node B. The scheduled grant is simply suitable
power allocated to the UE so it can transmit data at the desired QoS.
• E-RGCH: This can be sent by both serving and non serving RLS cells. All of these cells measure
the rise over thermal in the uplink and sends suitable power control commands to UE.
• E-HICH: This channel can be carried by both the serving and non-serving RLSs. All serving and
non-serving Node Bs receive the high-speed uplink data form the UE. All E-DCH active set Node
Bs try to decode the packet. If the packet is received successfully, an ACK is sent. Otherwise a
NACK is transmitted.
Uplink channels for HSUPA operation include:
• E-DPDCH: Carries high-speed uplink data and scheduling requests
• E-DPCCH: Carries control information such as the E-TFCI and the retransmission sequence
number (this channel is always associated with the E-DPDCH)
Complete R6 Channels (continued)
5-44
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Complete R6 Channels Complete R6 Channels (continued)(continued)
UE
C10High Speed Data and Signaling
E-DPDCH / E-DPCCH
Scheduling/Noise Control
E-AGCH/E-RGCH
Scheduling
E-RGCH
E-DPDCH / E-DPCCH
E-RGCH
E-HICH
E-HICH
E-HICHACK/NACK
E-DPDCH / E-DPCCH
DPDCH/DPCCHDPCH
DPDCH/DPCCH
DPCH
Voice, Data, Signaling / TPC, TFCI, Pilot
DPDCH/DPCCH
Voice, Signaling, TFCI, Pilot, TPC
DPCH
CQI, ACK/NACK
HS-DPCCH
High speed Control/Data
HS-SCCH/ HS-PDSCH
C11
C21
5-45
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
HSUPA uplink operations on the Enhanced Dedicated Channel (E-DCH) support two types of
transmission: Non-scheduled and Node B controlled scheduled. Let us discuss briefly both of these types.
1. Non-scheduled mode of E-DCH transmission: The Radio Resource Control (RRC) signaling
configures the UE to a maximum data rate. The UE may transmit up to this configured data rate at
any time. This is simple and easy to implement from a UE’s perspective. It is also suitable for
sending signaling messages on the signaling radio bearer as well as transmitting user traffic for
guaranteed bit rate types of services. The non-scheduled transmission type reduces the signaling
overhead and shortens the scheduling delays for time critical, low data rate services. However, it
increases the complexity of implementation at the RNC admission control. Another negative factor
is that it reduces the radio link throughput on the uplink since admission control and load
management functions assume the peak rate transmissions for their computation. The UE may not
have data to send all the time, which results in underutilized reserved radio resources.
2. Node B controlled Scheduled E-DCH transmission: E-DCH active set members schedule grants
(i.e., power allocations to UEs for uplink data transmissions on the E-DCH). The serving E-DCH
cell may allocate absolute grants based on its reverse link interference measurements, which tell
the UE the maximum power offset it can use for uplink E-DPDCH transmission with respect to the
power-controlled DPCCH channel. Non-serving DCH cells may measure their reverse link
interference and influence a UE on the reverse link transmission rates and power. A non-serving
E-DCH RL may cause the UE uplink reverse link transmission rates to go down if the cell’s uplink
RoT is very high. Serving E-DCH RLS members may cause the uplink transmission rates to go
up, go down, or stay the same based on their own RoT measurements. As can be seen, the
scheduled approach is very dynamic, and, hence, can result in better uplink performance for each
cell. However, the cost of this approach is the increased signaling overhead on the air interface and
the complexity and delay introduced due to the centralized scheduling at each cell.
Uplink Transmission
5-46
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Uplink Transmission Uplink Transmission Types of Uplink
TransmissionNon-
ScheduledNode B
Controlled
• E-DCH may transmit up to a configurable rate any time
• SRBs & GBR servicesPros:• Minimal signaling overhead
& short scheduling delayCons:• Complexity of
implementation & sub-optimal throughput
• Scheduling grants controlled by Node Bs
• All other servicesPros:• Better performanceCons:• Increased signaling
overhead & scheduling delay
5-47
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This slide provides a high level picture of a typical Node B controlled scheduled mode Enhanced
Dedicated Channel (E-DCH) operation. Once a UE has been assigned the E-DCH for uplink data
transmission, the UE follows these steps:
1. The UE looks at its buffer status for each logical channel and sends a scheduling request to the
serving cell. The request information includes the logical channel identity, buffer status and the
available power ratio at the UE.
2. The serving E-DCH cell in the E-DCH active set typically provides a power allocation or grant to
the UE. The allocation can be an absolute grant from the E-DCH serving cell. Members of the
serving E-DCH RLS may send an UP, DOWN or HOLD relative grant command to the UE. Non-
serving E-DCH Active Set members may send a HOLD or DOWN command to help maintain
their reverse link load levels. The type of grants sent from the serving E-DCH cell is
implementation-dependent. The network may send absolute and relative grants either at the
request of the UE or autonomously to react to changing reverse link load conditions.
3. The UE receives the grant information from different active set members. The UE goes through a
deliberate process to identify the reverse link data rate for transmission based on the following:
• The current serving grant
• Data in buffer logical channels in priority order
• The available power ratio for the E-DCH transmission with respect to the power
controlled DPCCH channel
4. The UE transmits the data on E-DCH/E-DPDCH channels and the associated physical layer
control information on the E-DPCCH.
Uplink Data Transmission Overview
5-48
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Uplink Data Transmission OverviewUplink Data Transmission Overview
UE UTRAN
2. Absolute and Relative Grants
(E-AGCH and E-RGCH)(Autonomous or in response to Scheduling Request)
4. Data and Control Info
(E-DCH and E-DPCCH)
5. ACK or NACK
(E-HICH)
3. Data Rate Selection at UE
(E-DCH and E-DPCCH)(Scheduling Request: Logical Channel, Buffer Occupancy,
Available Power Ratio)
1. Scheduling Information and Happy Bit
5-49
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
5. Active set member cells receive and process the information to determine whether the packet can
be decoded correctly. Each processing cell makes a determination whether an ACK or NACK
will be sent on the E-DCH Hybrid ARQ acknowledgement Indicator Channel (E-HICH) in
response to the received data on the E-DPDCH. Please keep in mind that cells in the same Node B
perform digital combining before the decoding process, and send the same ACK/NACK value. If
one of the cells sends an ACK to the UE, the HARQ process at the UE clears the buffer for the
packet and prepares for transmission of the next packet.
This sequence is repeated for every TTI cycle as needed. Please note that steps 1 and 2 may not be
required for each TTI transmission.
Uplink Data Transmission Overview (continued)
5-50
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Uplink Data Transmission Overview Uplink Data Transmission Overview (continued)(continued)
UE UTRAN
2. Absolute and Relative Grants
(E-AGCH and E-RGCH)(Autonomous or in response to Scheduling Request)
4. Data and Control Info
(E-DCH and E-DPCCH)
5. ACK or NACK
(E-HICH)
3. Data Rate Selection at UE
(E-DCH and E-DPCCH)(Scheduling Request: Logical Channel, Buffer Occupancy,
Available Power Ratio)
1. Scheduling Information and Happy Bit
5-51
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Let’s discuss the scheduling request information transmitted by the UE. What information is sent by UE as
part of scheduling requests?
• Highest Priority Logical Channel ID (HLID - 4 bits): Identifies the highest priority logical
channel that has data available in its buffer.
• Total Enhanced Dedicated Channel (E-DCH) Buffer Status (TEBS - 5 bits): Identifies the total
amount of data available across all logical channels. This field corresponds to the amount of data in
bytes that is available for transmission and re-transmission in the RLC layer.
• Highest Priority Logical channel Buffer Status (HLBS - 4 bits): Indicates the amount of
available data from the highest priority logical channel ID relative to the highest buffer size value
reported by the TEBS field.
• UE Power Headroom (UPH - 5 bits): Indicates the maximum UE transmission power and
corresponding DPCCH code power. The maximum UE power is the lowest maximum UL
transmission power allowed in a cell and maximum power capability of the UE determined by the
power class of the mobile.
– The UE might send a feedback bit called a “Happy Bit” on the E-DPCCH for every E-
DCH transmission. The UE may be unhappy if it is transmitting as much scheduled data as
allowed by the serving grant and it has enough power available to transmit at a higher data
rate, and TEBS requires more than the Happy_Bit_Delay_Condition. The
Happy_Bit_Delay_Condition is a timer in ms transmitted by the SRNC in a Radio Bearer
Setup message.
Transmission of Scheduling Requests
5-52
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Transmission of Scheduling RequestsTransmission of Scheduling Requests
UE
Node B
Serving RLSRNC
Scheduling Request infoMAC-e
E-DCH
UPH TEBS HLBS HLID5 bits 5 bits 4 bits 4 bits Scheduling
info
How?• Stand alone tx• Along with data tx • Happy Bit on E-DPCCH
When?• No scheduling grant available: data needs to be sent• Scheduling grant periodically - RB Setup message
Scheduling info part of MAC-e header
5-53
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
• The UE sends the scheduling request if it has data to send and has no serving grant available. This
allows the active set E-DCH cells to schedule grants for the UE to enable data transmission on the
uplink in a timely manner. Even if a UE has a serving grant available for current transmission, the
UE may periodically send scheduling requests to update the scheduler at the Node B of its
changing status. This allows the schedulers at the Node B to obtain an up-to-date picture of the
current state of the UE and its buffers to help with ongoing scheduling decisions to better utilize the
uplink.
• The UE may send scheduling information on the MAC-e PDU either as a standalone transmission
or piggybacked with the MAC-e PDU data.
• The happy bit is sent by the MAC-e layer at the UE to the physical layer, which further inserts this
bit on the E-DPCCH whenever E-DCH transmission occurs.
Transmission of Scheduling Requests (continued)
5-54
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Transmission of Scheduling Requests Transmission of Scheduling Requests (continued)(continued)
UE
Node B
Serving RLS
Scheduling Request infoMAC-e
E-DCH
UPH TEBS HLBS HLID5 bits 5 bits 4 bits 4 bits Scheduling
info
How?• Stand alone tx• Along with data tx • Happy Bit on E-DPCCH
When?• No scheduling grant available: data needs to be sent• Scheduling grant periodically- RB Setup message
Scheduling info part of MAC-e header
RNC
5-55
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
An example of how and when the UE sends a scheduling request to the Node B is illustrated in this slide.
This is the initial process executed by the UE to request a grant from the Node B.
The UE has been assigned a primary E-RNTI 1 and secondary E-RNTI 2 on the Radio Bearer Setup
message. Please note several UEs can be assigned one primary E-RNTI. The Node B may also treat the
current scheduling Request from a UE differently from other UEs in the serving cell. This may be based on
the current attributes of scheduling request information. Therefore, the Node B may assign a grant with a
secondary E-RNTI value to that UE.
From higher layers, the MAC-e layer at the UE receives the following:
• Logical channel identifier
• Its priority (HLID)
• The Total Enhanced Dedicated Channel (E-DCH) buffer status (TEBS)
• The percentage of highest logical channel buffer occupancy relative to all logical channel buffers
waiting to be transmitted (HLBS)
• Power Headroom (UPH), which is the ratio of maximum power allowed for UE-to-DPCCH code
power
The UPH also provides the UE with enough power on the uplink to send data at a high rate. This process
triggers the transmission of the happy bit on the E-DPCCH. The UE is unhappy if it has enough power
headroom to transmit data at a much higher rate. The UE shows its unhappiness by sending a happy bit = 0
on the E-DPCCH physical channel. The status of the happy bit is indicated by the MAC-e to the physical
layer.
Sending Scheduling Request - Example
5-56
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Sending Scheduling Request Sending Scheduling Request -- Example Example UE
Physical Layer Functions
MAC-d
Node BDTCH 1 DTCH 2
Priority 1 Priority 2
Logical channel id =1
HLID= 1TEBS=30 bytes
HLBS= 75%UPH= 8db
Logical Channel
ID=2HLID=2
TEBS=30 bytes
HLBS= 25%
Happy Bit = 0 Unhappy
MAC e/ es
Physical Layer Functions
E-DCH scheduling
E-DCHcontrol
MAC-e
0001 00101 1110 01000
HLID TEBS HLBS UPH
Scheduling Request info
E-DPDCH
E-DPCCH (Happy Bit = 0)
SG
(Pri E-RNTI 1, Sec E-RNTI 2)
MAC- e PDU
Serving Node B
5-57
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
In this example, there are 2 Logical channels: 1 and 2. Logical channel ID 1 has priority 1 and logical
channel ID 2 has priority 2. As a result, logical channel ID 1 has higher priority.
Therefore, HLID is set to 1-0001 (4 bits). The total E-DCH buffer status for logical channel ID 1 and 2 is
30 bytes. As a result, TEBS is set to 30 bytes. From 25.321 specs, 30 bytes corresponds to index 5 (00101,
5 bits).
The highest logical channel buffer (i.e., the logical channel ID 1 buffer) has approximately 75% of the total
E-DCH buffer data to be transmitted. From 25.321, 75% corresponds to index 14 (1110, 4 bits). The UE
has 8 db of power headroom (01000, 5 bits) to transmit data at a much higher rate. In this example, it is
assumed that the UE is utilizing the current serving grant relative to the TEBS to its maximum over
happy_bit _delay_ condition. The UE has enough data to send from its highest priority logical channel and
equally enough uplink power headroom to transmit at a higher data rate. This triggers the UE to feel
unhappy and it indicates the status on the E-DPCCH. Therefore, the UE forwards the Scheduling Request
message, which is part of the MAC-e PDU on the E-DPDCH physical channel. The E-DCH control at the
Node B receives the scheduling request information and forwards it to the E-DCH scheduling block at the
MAC-e layer of the Node B. The Node B may now assign a scheduling grant to the UE.
Sending Scheduling Request - Example (continued)
5-58
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Sending Scheduling Request Sending Scheduling Request -- Example Example (continued)(continued)
UE
Physical Layer Functions
MAC-d
Node BDTCH 1 DTCH 2
Priority 1 Priority 2
Logical channel id =1
HLID= 1TEBS=30 bytes
HLBS= 75%UPH= 8db
Logical Channel
ID=2HLID=2
TEBS=30 bytes
HLBS= 25%
Happy Bit = 0 Unhappy
MAC e/ es
Physical Layer Functions
E-DCH scheduling
E-DCHcontrol
MAC-e
0001 00101 1110 01000
HLID TEBS HLBS UPH
Scheduling Request info
E-DPDCH
E-DPCCH (Happy Bit = 0)
SG
(Pri E-RNTI 1, Sec E-RNTI 2)
MAC- e PDU
Serving Node B
5-59
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The absolute grant and the relative grant are two types of grants sent by the Node B to the UE. The
absolute grant may be sent only by the serving Enhanced Dedicated Channel (E-DCH) cell to a UE. The
Node B scheduler makes the decision on the absolute grant for a UE based on multiple parameters:
• QoS requirements for the current packet data service
• Measured uplink interference level (RoT)
• The scheduling request that contained information on the logical channel data waiting in the buffer
to be sent by the UE
Absolute grants sent by the serving E-DCH cell contain:
• E-DCH Radio Network Temporary Identifier (E-RNTI): The E-RNTI is a 16-bit identifier
allocated by the SRNC to identify the UE on the E-DCH transmissions. The network may assign
the same E-RNTI value to one or more UEs. Each UE may also be assigned a primary E-RNTI and
a secondary E-RNTI. The E-RNTI assignments are performed using RRC signaling messages.
When grants are sent over the air on the E-AGCH, the grant recipient is identified within the
contents by masking the CRC of the contents with an E-RNTI value. This ensures that the grants
are properly processed by only the intended recipients (i.e., UEs that have been allocated the E-
RNTI).
• Maximum power ratio: A 5-bit value that identifies the maximum E-DPDCH/DPCCH power
ratio that the UE may use for E-DCH transmission.
• HARQ Process Activation flag: This bit is used in different ways. One use is to indicate a switch
between primary and secondary E-RNTI usage. This bit is also used for process activation of the
HARQ processes. In other words, this bit indicates whether the primary absolute grant (i.e., the
absolute grant sent with the primary E-RNTI as the identifier) is activating or deactivating one or
all of the HARQ processes. Please note that each HARQ process is responsible for sending a
packet on the E-DCH.
Transmission of Grants by the Node B
5-60
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Transmission of Grants by the Node BTransmission of Grants by the Node B
Uplink RoT
Uplink RoT
QoS from SRNC
Scheduling request from UE
Absolute Grant(E-AGCH)
Relative Grant (E-RGCH)
MAC- e
Physical Layer
Serving Cell
Node B
MAC- e
Physical Layer
Serving and non-serving Cell
Node B
E-RNTI
Max. allowed power ratio
HARQ flag
16 bits
5 bits1 bit
• (UP=+1, HOLD =0, or DOWN=-1) for serving cell
• (HOLD=0 or DOWN=-1) for Non-serving cell
• 1 or more UEs• Same E-RGCH can be assigned to
multiple UEs
5-61
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Relative grants may be sent by the Node B scheduler to all the UEs that include this cell in their Enhanced
Dedicated Channel (E-DCH) active set. However, the commands that are sent as relative grants change
from a serving E-DCH RLS to a non-serving E-DCH RLS. The relative grant communicates the following
to the UE:
• The relative grant, like the absolute grant, may be sent to one or more UEs
• Relative grants are used in conjunction with absolute grants and serve as a complement to absolute
grants
• Relative grant commands differ for serving E-DCH active set members and non-serving E-DCH
Active Set members
– Serving E-DCH RLS member cells can send an UP, DOWN or HOLD relative grant
command to a UE
– Non-serving E-DCH cells may send a DOWN (to manage the rising RoT on their uplink) or
a HOLD command (which essentially is DTXed, and, hence, is not really a feedback)
Transmission of Grants by the Node B (continued)
5-62
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Transmission of Grants by the Node BTransmission of Grants by the Node B(continued)(continued)
Uplink RoT
Uplink RoT
QoS from SRNC
Scheduling request from UE
Absolute Grant(E-AGCH)
Relative Grant (E-RGCH)
MAC- e
Physical Layer
Serving Cell
Node B
MAC- e
Physical Layer
Serving and non-serving Cell
Node B
E-RNTI
Max. allowed power ratio
HARQ flag
16 bits
5 bits1 bit
• (UP=+1, HOLD =0, or DOWN=-1) for serving cell
• (HOLD=0 or DOWN=-1) for Non-serving cell
• 1 or more UEs• Same E-RGCH can be assigned to
multiple UEs
5-63
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This example shows how serving and non-serving Node Bs schedule grants once they receive scheduling
requests from the UE.
The serving Node B uses the scheduling request information and uplink Rise over Thermal (RoT) to
determine the scheduling grant. The scheduling grant is nothing but the traffic-to-pilot ratio or the ratio of
E-DPDCH to E-DPCCH.
The first process involves measurement of total RoT by serving Node Bs and non-serving Node Bs. The
Measured RoT is compared with the predefined UL RoT threshold. Based on this comparison, the serving
Node B may assign an absolute grant or relative grant. The non-serving Node B assigns relative grants
based on the compared results. In this example, both the serving and non-serving Node Bs measure the
total uplink ROT and find that the measured value is below the UL ROT threshold.
In process number 2, the serving Node B determines the scheduling/serving grant and assigns a value of
20 db maximum E-DPDCH-to-E-DPCCH power. This information is sent on the E-AGCH physical
channel. The actual mechanism of how the serving grant is determined by the Node B and how the 20 db
value has been decided is beyond the scope of this example. This example shows only the processes
involved in transmitting grants to the UE.
The E-AGCH has 3 fields: Identity type (primary or secondary E-RNTI identifier, 16 bit string), maximum
power allowed (5 bits) and a grant scope or HARQ flag indicating whether the primary absolute grant (i.e.,
the absolute grant sent with the Primary E-RNTI as the identifier) is activating or deactivating one or all of
the HARQ processes.
In this example, the primary E-RNTI 1 has been signaled and the HARQ flag = 0, which indicates that all
HARQ processes are activated or deactivated by usage of the primary E-RNTI.
In addition to absolute grants, in process number 3 the serving Node B also signals a Power “HOLD”
command to the UE on the E-RGCH channel since the UL RoT measured has not exceeded the threshold.
For the non-serving Node B, the measured total ROT is below the threshold, which triggers the non–
serving Node B to send a power HOLD command to the UE on the E-RGCH channel. Please note that the
power UP command cannot be sent by any cell that is part of the non-serving RLS.
Scheduling and Grants - Example
5-64
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Scheduling and Grants Scheduling and Grants -- ExampleExample
UE ServingNode B
Scheduling Grant
E-AGCH
Scheduling
E-RGCH
HOLD
Noise Control
2
HOLD
E-RGCH3
UL E-DCH
3
Measured UL RoT below UL RoT
Threshold
Scheduling Request
Uplink RoT
Pri E-RNTI 1 Power=20db
HARQFlag =0
Measured UL RoT below UL RoT
Threshold
Non-servingNode B
Uplink RoT
1 1
5-65
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This slide depicts the data rate selection process at a UE. Prior to data transmission operations on the
Enhanced Dedicated Channel (E-DCH), the SRNC sets up configuration parameters using Radio Resource
Control (RRC) signaling for all logical channels, MAC-d flows and Hybrid ARQ (HARQ) processes
related to the E-DCH. Every TTI (2 ms or 10 ms), the UE executes the E-TFC selection algorithm. The
UE follows these steps to select the E-TFC:
1. The UE determines whether it has to take into account scheduled or non-scheduled grants for
upcoming transmission
2. The UE selects a MAC-d flow and identifies the MAC-d flows that can be multiplexed according
to the multiplexing list provided.
3. The UE identifies the power offset to use based on the HARQ profile of the selected MAC-d flow.
4. Once it calculates the power offset, it determines the maximum MAC-e PDU size or E-TFC that
can be transmitted in the next TTI.
5. The UE also uses a reference E-TFCI and its power offset to compare with the selected E-TFC.
The variation in these values may lead to a quality that cannot be sustained during upcoming
transmission. This huge variation may result in an E-TFC blocked state.
6. Among the E-TFCS selected, UE may use the smallest E-TFC that maximizes the transmission of
data for both the scheduled and non-scheduled grant.
The Node B also includes the number of transmissions that have been required to decode the PDU
correctly on each MAC-es PDU sent to the SRNC. So, the SRNC has an up-to-date power offset, which it
may decide to signal to the UE and the Node Bs in the E-DCH active set. These new power offset
attributes are for one or more MAC-d flows.
The resulting MAC-e PDU is transmitted during the next TTI. Now, the HARQ process for the next TTI
takes these as input values and forms the transport block. Turbo coding and related functions are executed
on the PDU. Data is then spread across the number of E-DPDCH channels required for the chosen data
rate. Data and related control information are then sent over the air using the necessary number of E-
DPDCHs and the associated E-DPCCH.
Data Rate Selection at the UE
5-66
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Data Rate Selection at the UEData Rate Selection at the UE
E-TFC Selection Algorithm (New Tx)
HARQ Functionality
Physical Layer
Priority per Logical Channel
E-DCH E-DPCCH
Absolute & RelativeGrants (Max Power
Ratio)
Current Flows for E-DCH
E-TFC & MAC-e PDU for next TTI HARQ profile
E-TFC RSN (Implicit Indication at RV)
Power OffsetMax # of
Retx
(RRC) HARQ Profile for each
MAC-d flow
Power Offset
Reference E-TFC Power Offset
MAC e / es
5-67
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The E-DCH Dedicated Physical Data Channel (E-DPDCH) carries the E-EDH transport channel. The E-
DPDCH supports both the 10 ms TTI and 2 ms TTI. If the 2 ms TTI is used, the E-DPDCH uses a 2 ms
subframe for transmission. Depending on the data rates required for uplink E-DCH transmission, the UE
may use one or more E-DPDCHs. The E-DPDCH uses a range of spreading factors to support different
data rates. For example, to support a 1.92 Mbps data rate, the E-DPDCH uses SF = 2. As the data rates go
down, the SF value goes up (i.e., more spreading gain). For example, when the desired data rate on the E-
DPDCH is 60 kbps, SF = 64 is used. The E-DPDCH is power-controlled by the Node B. In addition, soft
handover is supported on the E-DCH. To support soft handover, HSUPA defines the concepts of the
serving E-DCH cell, the serving E-DCH Radio Link Set (RLS) and the non-serving E-DCH RLS.
The serving E-DCH RLS is the set of sectors in the E-DCH active set from the Node B that includes the
serving E-DCH cell. The non-serving E-DCH RLs are the E-DCH active set cells that do not belong to the
E-DCH serving RLS.
E-DPDCH
5-68
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DPDCHDPDCH
1 Subframe = 2 ms
0 14. . .1 2
1 Radio frame = 10 ms
2560 chips10 x 2 (k+2) bits
k = 0..5
• E-DPDCH carries the E-DCH in 2 or 10 ms TTIs• There can be 1 or more E-DPDCHs per UE depending on
the data rate• Spreading Factor ranges from 2 (1920 kbps) to 256
(15kbps)
5-69
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
E-DPCCH contents transmitted in each slot are shown in this diagram. In each slot, 10 bits of information
are sent. These 10 bits of information are related to physical layer transmission characteristics and
feedback on the E-DCH.
1. E-DCH Transport Format Combination Indicator (E-TFCI): This field indicates the transport
format that was used by the UE on the E-DCH to the receiving Node B. the E-TFCI is similar to
the TFCI used in DCH transmission.
2. Retransmission Sequence Number (RSN): This field indicates the retransmission sequence
number of the packet that is being sent over the air. This is related to the Hybrid Automatic Repeat
Request (HARQ) processing of user traffic received on the E-DCH. The receiving HARQ process
understands the contents, and it uses this information to help with the decoding process.
3. Happy Bit: This is a one-bit feedback from the UE to the serving cell of the E-DCH to indicate
whether it is receiving enough transmission power grants to meet its transmission needs. This is
determined by the UE by comparing the buffered data size with the number of TTIs required to
transmit them. If the number of TTIs needed is more than a configured threshold, the UE sends an
“unhappy” bit!
E-DPCCH
5-70
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DPCCHDPCCH
1 Subframe = 2 ms10 bits
Transport format infoRetrans-mission
info
Statusinfo
• E-DPCCH carries control information associated with E-DCH• There is only one E-DPCCH for each UE• The Spreading Factor is always 256 (15 kbps)
1 Radio frame = 10 ms
0 141 2 13
5-71
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Let us discuss the E-DCH data transmission by the UE to the Node B. The data from the application and
PDCP reaches the RLC Layer. The RLC adds its own header and forwards the RLC PDU to the MAC-d
through the logical channel. The MAC-e already has a mapping table consisting of the logical channel,
MAC-d flow and MAC-d PDU size. The MAC-d PDU size is determined by the E-TFC selection
algorithm at the MAC-e. The mapping of the logical channel, MAC-d flow and MAC-d PDU size is
identified by the Data Descriptor Indicator (DDI, 6bits). The DDI is part of the MAC-e header.
The MAC-d PDUs are then transmitted to the MAC-es layer. Multiple MAC-d PDUs are concatenated
into MAC-es PDUs by the MAC-es layer, and it further multiplexes one or more multiple MAC-es PDUs
into a single MAC-e PDU. This functionality is handled by the Multiplexing and Transmission Sequence
Number (TSN) setting entity at the MAC–es layer. The TSN is a six-bit field that increments for every
MAC-es PDU transmitted on the air interface. The TSN is set for each logical channel and MAC-es PDU.
The TSN is header information inside the MAC-es PDU.
The MAC-es PDU is further forwarded to the MAC-e PDU, which adds the DDI and N as its header. N is
a 6-bit field that corresponds to consecutive PDUs corresponding to the same DDI value. The MAC-e
PDU is forwarded to the HARQ process entity at the MAC-e. The HARQ entity is responsible for storing
and retransmitting the MAC-e payload. It also provides the E-TFC, the Retransmission Sequence Number
(RSN) and the power offset to be used by physical layer. The physical layer derives the RSN, Connection
Frame Number (CFN) and the subframe number, in the case of a 2 ms TTI. All of these parameters are
required by the physical layer to transmit the HARQ processes. The HARQ entity can use the RV derived
from the RSN table or RV = 0 for every transmission, if signaled by the Radio Resource Control (RRC).
Finally, the HARQ data is sent in the next TTI. The MAC-e PDU is now forwarded to the physical layer,
which further adds its own header information. The final data is sent on the E-DPDCH physical channel.
E-DCH Transmission from the UE
5-72
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DCH Transmission from the UEDCH Transmission from the UE
Numbering
DTCH 1 DTCH 2
RLC AM/UM
Numbering
MAC-es/e
MAC- D flowsMAC-d flow 1
MAC-d flow 2
Header Data
Data
TSN Data
DDI N Data
Physical layer FunctionsE DPDCH
E-DPCCH /DPCH
RLC PDU
MAC PDU
MAC-es PDU
MAC-e PDU
Data E-DCH
MAC-d
DCCH
HARQ process
Multiplexing/TSN setting
5-73
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Let us discuss how the UTRAN receives E-DCH data from the UE.
The physical layer at the Node B receives the E-DCH information on the E-DPDCH. The physical layer at
the Node B removes its header information and forwards the MAC-e PDU through the E-DCH transport
channel. The MAC-e PDUs from layer 1 are forwarded to the HARQ entity at the MAC-e in the Node B.
The HARQ entity handles multiples instances of Stop-and-Wait HARQ protocols. Each HARQ process
tries to decode the packet received from the physical layer. If the reception is successful, then an ACK is
generated by the HARQ entity; otherwise a NACK is sent.
The successfully decoded MAC-e PDUs are forwarded to a demultiplexing function at the MAC-e in the
Node B. This function demultiplexes the MAC-e PDUs into MAC-es PDUs and forwards them to the
associated MAC-d flow. The DDI value sent on the MAC-e header from the UE helps the Node B MAC-e
forward MAC-es PDUs to the corresponding MAC-d flow. The Node B already has the configuration of
the DDI mapping to the MAC-d flow and MAC-d PDU size. The DDI and N are also sent to the MAC-es
at the RNC by the MAC-e on the Iub FP.
The MAC-es already has the mapping of the logical channel to the MAC-d flow and MAC-d PDU size.
Based on the DDI value and N sent by the Node B to the RNC, the MAC-es can determine from the table
which logical channel this MAC-d flow belongs to. The re-ordering queue distribution function is
responsible for routing the MAC-es PDUs to the correct re-ordering buffer. Each logical channel has a re-
ordering buffer. In fact, the DDI, N and Logical channel mapping is handled by the re-ordering queue
distribution function.
Once the MAC-es PDUs reach the re-ordering buffer, the MAC-es reorders its PDUs based on the TSN
transmitted by the UE on the MAC-es header and the Node B-tagged CFN. Once the MAC-es PDUs are
reordered they are delivered to the disassembly function of the MAC-es. This function removes the MAC-
es header and forwards the MAC-d PDUs to the MAC-d layer. The MAC-d further forwards it to the RLC,
which strips its header sends it to the PDCP.
E-DCH Reception at the UTRAN
5-74
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DCH Reception at the UTRANDCH Reception at the UTRANNode B RNC
RLC AM/UMDTCH 1 DTCH 2 DCCH
Physical Layer Functions
MAC-d
Dis-Assembly
Re-Ordering
MAC- es
MAC-d flows
De-Multiplexing
HARQ Profile per MAC-d flow
MAC-d flow=1
MAC-d flow=2
MAC-e
E-DPDCH E-DPCCH
Data
DDI N Data
TSN Data
Data
Header Data RLC PDU
MAC-d PDU
MAC-es PDU
MAC –e PDU
DDI,N (Iub-FP)
E-DCH
Reordering queue
distribution
Reordering queue
distribution
MAC-d flows
5-75
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This block diagram provides a high level flow of what happens to user data processed within the E-DCH
transport channel. When the UE E-TFC selection algorithm picks a new packet for transfer over the air, the
transport block experiences the following steps prior to physical channel handling:
• A 24-bit CRC is calculated and attached to the data to be sent over the air
• A transport block is formed with a maximum block size of 5114 bits for input into the turbo coder
• Channel coding is done using the R = 1/3 rate turbo coder
• Physical layer Hybrid ARQ (HARQ) processing is performed. The rate matching function is
executed, which produces the subset of turbo coder output bits to match the requirements of the E-
DPDCH physical channels. Moreover, the bit selection process has 4 redundancy versions to
choose from. Each option prioritizes different combinations of systematic and parity bits from the
turbo coder output.
• The last step in E-DCH transport channel processing is segmenting the bits for the required number
of E-DPDCH physical channels. Once the data bits are segmented, block interleaving is performed
to add some time diversity to radio link transmission of the data.
• Next, the appropriate spreading codes are used to spread the data, and the UE scrambling code is
applied to scramble the data to make it ready for air interface transmission.
E-DCH Transmission Strategy
5-76
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DCH Transmission Strategy DCH Transmission Strategy
(E-TFC)(Turbo, Rate = 1/3)
CRC Attachment
Channel Coding
HARQ Rate
Matching
Physical Channel
Segmentation & Interleaving
E-DPDCH
Node B
Node B
Serving RLS
Non-Serving RLS
E-TFCI7 bits
RSN 2 bits
UE
Channel Coding
Physical channel Mapping
E-DPCCH
E-HICHACK=+1, NACK=-1
E-HICHACK=+1, NACK=0
1 Happy bit
5-77
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Let’s look at the contents of the E-DPCCH transmission. The E-DPCCH should transmit the control
information to help the receiving cell identify and retrieve contents of the E-DCH. The following two key
pieces of information are sent within the E-DPCCH:
1. The Retransmission Sequence Number (RSN) is a 2-bit sequence number used to identify the
transmitted data and help avoid or prevent soft buffer corruption at the receiver. The uplink HARQ
transmissions are based on a synchronous model for retransmission. The RSN is a 2-bit value and,
hence, if the receiver loses 3 consecutive retransmission packets, the subsequent data received may
be incompatible with buffered data for the same HARQ process. Therefore, the Node B should
avoid the soft buffer corruption problem by flushing the buffer when 3 consecutive RSN
transmissions are lost.
2. Each transmission identified by the RSN may send different parts of the coded data as dictated by
one of four possible RV values. The UE may be signaled by the Radio Resource Control (RRC) to
use only an RSN value of 0. In this case, the RV prioritizes the systematic bits and retransmits
exactly the same information in each retransmission. The second option is that the RV index to be
used for the next transmission through the HARQ process is determined by the RSN. A mapping
between the RSN and RV index is defined in the standards, and this mapping is used by the UE to
determine the set of bits to transmit. Also, the receiver (Node B) can guess the bit positions of the
received bits by looking at the received RSN on the E-DPCCH.
3. Another key piece of information transmitted on the E-DPCCH is the E-TFCI value. The E-TFCI,
which is a 7-bit index value, specifies the payload size.
Let’s look at the behavior of HARQ processes at the UE. The idea of HARQ (and E-DCH) is to transmit
information packets without errors.. The UE receives the E-HICH channel ACK or NACK from each of
the serving RLSs and non–serving RLSs. The ACK/NACK is sent by the E-HICH physical channel. For
the serving RLS E-HICH, the ACK corresponds to +1 and the NACK corresponds to -1. For the non-
serving RLS, the ACK corresponds to +1 and the NACK corresponds to 0.
E-DCH Transmission Strategy (continued)
5-78
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DCH Transmission Strategy DCH Transmission Strategy (continued)(continued)
(E-TFC)(Turbo, Rate = 1/3)
CRC Attachment
Channel Coding
HARQ Rate
Matching
Physical Channel
Segmentation & Interleaving
E-DPDCH
Node B
Node B
Serving RLS
Non-Serving RLS
E-TFCI7 bits
RSN 2 bits
UE
Channel Coding
Physical channel Mapping
E-DPCCH
E-HICHACK=+1, NACK=-1
E-HICHACK=+1, NACK=0
1 Happy bit
5-79
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
There are 3 types of reconfiguration methods used in UMTS. All three methods have been enhanced at the
Radio Resource Control (RRC) to support HSUPA.
1. Radio Bearer Reconfiguration, which is required when there are the following changes:
• When the Quality of Service (QoS) changes, such as the addition of a new service to the
old service. This is very common in UMTS and reconfiguration happens frequently
throughout the lifecycle of a call. Multi services like circuit-switched calls with HSUPA
can occur simultaneously. Therefore, if a circuit-switched call is already established and an
HSUPA call is added to an existing circuit-switched call, radio bearer reconfiguration is
performed by the RRC. This message adds a new E-DCH transport channel with
corresponding E-DCH MAC-d flows and logical channel priorities.
• Change of RLC content
• Change of TFS/TFCS
• Assignment/release of physical channels
Reconfiguration Types and Functions
5-80
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Reconfiguration Types and FunctionsReconfiguration Types and Functions
• Change of QoS• Change of RLC
content • Change of TFS/TFCS• Assignment/release
of physical channels
• Changes in traffic volume
• Changes in TFS• Use of new
transport channel• May change
physical
• Changes in RRC states
• Changes in DL CC• No transport channel
type switching
Radio BearerReconfiguration Transport Channel
ReconfigurationPhysical ChannelReconfiguration
Reconfiguration
5-81
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
2. Transport channel reconfiguration
The transport channel is required when the following changes occur:
• Changes in traffic volume
• Changes in TFS
• Use of a new transport channel
• Change in physical channel bandwidth
3. Physical Channel Configuration
Physical channel reconfiguration can be required when the following changes occur:
• Changes in Radio Resource Control (RRC) states like moving from the cell DCH to the
cell FACH state
• Changes in DL Channelization codes
Physical channel reconfiguration cannot be performed when transport channel switching occurs.
Reconfiguration Types and Functions(continued)
5-82
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Reconfiguration Types and FunctionsReconfiguration Types and Functions(continued)(continued)
Radio BearerReconfiguration Transport Channel
ReconfigurationPhysical ChannelReconfiguration
Reconfiguration
• Change of QoS• Change of RLC
content • Change of TFS/TFCS• Assignment/release
of physical channels
• Changes in traffic volume
• Changes in TFS• Use of new
transport channel• May change
physical
• Changes in RRC states
• Changes in DL CC• No transport channel
type switching
5-83
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The following example shows the message sequence flow explaining the setup of the E-DCH
configuration. Also, the TTI reconfiguration is shown in the same scenario.
1. The RNC receives the RAB Assignment Request RANAP message from the SGSN requesting a
specific QoS. The RNC requests the Node B to prepare for reconfiguration and configuration of
the E-DCH.
2. The RNC transmits a request to the E-DCH serving Node B to perform a synchronized radio link
reconfiguration using the NBAP Radio Link Reconfiguration Prepare message for the E-DCH
radio link. It includes information regarding DCHs to Delete IE, the serving E-DCH RL ID, and
the E-DCH FDD.
3. The E-DCH Node B responds with the NBAP Radio Link Reconfiguration Ready message, which
includes the DCH Information Response, E-DCH FDD Information Response and the E-RNTI.
4. The RNC initiates setup of a new Iub Data transport bearer using the ALCAP protocol. The
parameters include the AAL2 Binding Identity to bind the Iub data transport bearer to the E-DCH.
5. The RNC then transmits the NBAP Radio Link Reconfiguration Commit message to the E-DCH
Node B, which includes the activation time. It consists of the RNC selected activation time in the
form of a CFN.
6. The RNC then transmits a Radio Resource Control (RRC) Radio Bearer Reconfiguration message
to the UE, which includes activation time, E-DCH information and the E-RNTI.
7. The UE responds with the RRC Radio Bearer Reconfiguration Complete message to the RNC.
E-DCH Configuration
5-84
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DCH Configuration DCH Configuration UE RNC GGSNSGSNNode B
2. Radio Link Reconfig Prepare
3. Radio Link Reconfig Ready
5. Radio Link Reconfig Commit
4. ALCAP Iub Data Trans. Setup EDCH
6. Radio Bearer Reconfiguration
7.Radio Bearer Reconfig Comp
QoS modification1. RAB Assign. Req.
5-85
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This slide explains E-DCH TTI reconfiguration.
8. The RNC transmits the NBAP Radio Link Reconfiguration Prepare message to request the E-
DCH Node B to perform a synchronized radio link reconfiguration for the E-DCH radio link.
9. The E-DCH Node B responds to the RNC with the Radio Link Reconfiguration Ready message,
which consists of the E-DCH FDD Information Response.
10. The RNC then transmits the NBAP Radio Link Reconfiguration Commit message to the E-DCH
Node B, which includes the RNC selected activation time in the form of a CFN.
11. The RNC also sends the Radio Bearer Reconfiguration message to the UE, including activation
time, E-DCH information (TTI change) and the E-RNTI.
12. The UE responds with a Radio Resource Control (RRC) Radio Bearer Reconfiguration Complete
message, which is sent to the SRNC.
E-DCH TTI Reconfiguration
5-86
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DCH TTI Reconfiguration DCH TTI Reconfiguration UE RNC GGSNSGSNNode B
9. Radio Link Reconfig Prepare
10. Radio Link Reconfig Ready
11. Radio Link Reconfig Commit
12. Radio Bearer Reconfiguration
13. Radio Bearer Reconfig Complete
8. ALCAP Iub Data Trans. Release DCH
5-87
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Radio Bearer Release is also enhanced in the Radio Resource Control (RRC) to support HSUPA. The
Radio Bearer Release can simultaneously release a service and reconfigure another service if two services
are accessed by the UE simultaneously.
This example depicts release of a radio access bearer on an Enhanced dedicated channel (E-DCH).
1. The SGSN initiates release of the radio access bearer with the RANAP Radio Access Bearer
Assignment Request message.
2. The RNC initiates release of the Iu Data Transport bearer between the CN and the SRNC using the
ALCAP protocol.
3. The RNC than sends requests to the Node B to prepare release of the E-DCH carrying the radio
access bearer Radio Link Reconfiguration Prepare message, which consists of E-DCH
information, the E-DCH serving cell ID, and the E-DCH MAC-d flows to delete.
4. The Node B responds to the RNC that release preparation is ready by transmitting the Radio Link
Reconfiguration Ready message.
5. The RNC then sends the NBAP Radio Link Reconfiguration Commit message to the Node B.
6. The RRC Radio Bearer Release message is sent by the RNC to the UE, which includes E-DCH
information, the E-DCH serving cell ID, and the E-DCH MAC-d flows to delete.
Radio Bearer Release
5-88
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Radio Bearer ReleaseRadio Bearer ReleaseUE RNC GGSNSGSNNode B
3.RL Reconfig. Prep.
6.Radio Bearer Release
5. RL Reconfig. Commit
4.RL Reconfig. Ready
Apply new transport format set
1.RAB Assign. Req.
2. ALCAP Iu Data Trans. Bearer Release
5-89
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
7. The UE sends the Radio Resource Control (RRC) Radio Bearer Release Complete message to the
RNC.
8. The RNC initiates release of the Iub (Serving RNS) Data Transport bearer using the ALCAP
protocol. Unused resources in the RNC and Node B are thereby released.
9. The RNC sends an acknowledgement of the released radio access bearer by transmitting the Radio
Access Bearer Assignment Release message.
Radio Bearer Release
5-90
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Radio Bearer ReleaseRadio Bearer ReleaseUE RNC GGSNSGSNNode B
8. ALCAP Iub Data Trans Bearer Release
9. RAB Assignment (Rel.)
7. Radio Bearer Release Comp
5-91
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This example illustrates a soft handover where the traditional R99 active set and E-DCH-reduced active set
are contrasted. The R99 active set contains the Node Bs that have R99 channels in uplink and downlink
soft handover. As is the case with R99, during a soft handover the Node B in the active set transmits data
to the UE and receives data from the UE. The UE and the Node B carry out maximal ratio combining
while the RNC performs selection combining in the uplink.
In the beginning, the UE is communicating with Node B1. The Active Set at this time contains Node B1
only. The UE continues to monitor pilot strengths from the neighbor Node Bs (Node B2, B3 and B4 in the
diagram). As the UE moves away from Node B1 and toward a neighbor Node B, Node B2, it finds Node
B2 and Node B3 capable of providing a good quality signal. Hence, the RNC makes Node B1, Node B2,
and Node B3 part of the R99 active set. The RNC then creates a subset of the active set and forms the E-
DCH active set of Node B1 and Node B2. Now, the R99 channels between the UE and the UTRAN (with
Node B1, Node B2, and Node B3) experience soft handover, while the E-DCH is in soft handover with
only Node B1 and Node B2.
Soft Handover
5-92
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Node B4
Soft HandoverSoft Handover
Node B 3
Node B 1
Node B2
Initial Communication
1
SimultaneousCommunicationwith Multiple Node Bs
2
3
R99 Active Set: {Node B1, 2, 3}E-DCH Active Set: {Node B1, 2}
5-93
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The creation of the E-DCH active set by the RNC is not standardized and thus implementation-specific.
The network infrastructure vendor can implement any suitable algorithm to provide product
differentiation. The RNC can choose the cells that provide the best uplink throughput so that the user-
perceived throughput is high. The RNC can also look at the available radio resources and the Quality of
Service (QoS). For example, if a substantial number of resources are available, higher E-DCH data rates
can be supported. One of the E-DCH active set members is chosen to be the E-DCH serving cell, and the
RNC can choose the cell with the best downlink quality (e.g., with the largest pilot (Ec/N0) among the E-
DCH active set members). The overall E-DCH handover process still relies on Radio Resource Control
(RRC) signaling as is the case with R99. The RNC allocates resources such as E-RNTI, HARQ processes,
serving grant (i.e., the allowed uplink resource for high-speed data transfer), and the radio channels
associated with the E-DCH. Recall that the E-RNTI is the temporary identity of the UE that has an E-DCH
operation set up with the RNC. Transmission of one new packet is the responsibility of one HARQ
process. The RNC can configure a suitable number of processes to enable the UE to continuously send
data in the uplink.
E-DCH Handover Algorithm at the RNC
5-94
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DCH Handover Algorithm at the RNCDCH Handover Algorithm at the RNC
RNCHandover
Algorithm forE-DCH Active Set
Implementation-specific
Algorithm
RRC-signaling based UTRAN-
based handover
Possible criteria for E-DCH Serving Cell and Serving RLS: (i) RLS with
highest UL throughput potential & (ii) Serving Cell: Best Downlink Quality
Resource Allocation (E-RNTI, HARQ Processes, Serving Grant, Radio
Channels)
5-95
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
There are several ways to convey the handover decision of the RNC to the UE. The E-DCH handover
process again reuses the existing mechanisms to indicate the change in the active set for both R99 and R6
to the UE. Examples of the messages that the RNC may send to the UE include the Radio Bearer
Reconfiguration and Active Set Update. It is possible to send a single message that indicates both an
HSDPA cell change and an E-DCH Active Set change. The E-DCH-specific information carried in the
messages includes the following:
• UE Identities: Primary and secondary E-RNTI
• Allocated Radio Channels in all E-DCH Active Set Cells: Examples of the contents include the
serving grant, primary vs. secondary grant selector, E-DPCCH/EDPCCH power offset, E-DPDCH
reference E-TFCI set, HARQ process allocation, E-AGCH channelization code, E-HICH DL
scrambling code, E-HICH channelization code, E-HICH signature sequence, E-RGCH signature
sequence, F-DPCH time offset, F-DPCH code number, and the F-DPCH TPC command error rate
target.
• Indicator of the Serving (or scheduling) E-DCH Radio Link: This informs the UE what the
serving cell is via P-CPICH information.
Conveying the Handover Decision
5-96
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Conveying the Handover DecisionConveying the Handover Decision
UE RNC
E-RNTI (Primary,
Secondary)
E-DPCH, E-DPDCH, E-AGCH, E-RGCH,
E-HICH, and F-DPCCH info
SchedulingE-DCH Cell Indicator
Physical Channel Reconfiguration(Intra-Node B Hard Handover: HSDPA, Soft Handover: HSUPA)
Transport Channel Reconfiguration(Inter-Node B Hard Handover: HSDPA, Soft handover: HSUPA)
Active Set Update(R99 + R6)
5-97
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
If any of the primary CPICHs within the reporting range becomes better than the previously best primary
CPICH, the UE sends a measurement report if the event 1D is ordered by the UTRAN.
The hysteresis parameter may be connected with each reporting event. The value of the hysteresis is given
to the UE in the reporting criteria field of the Measurement Control message.
In the example, the hysteresis ensures that the event 1D (primary CPICH 2 becomes the best cell) is not
reported until the difference is equal to the hysteresis value. The fact that primary CPICH 1 becomes best
afterward is not reported at all in the example since the primary CPICH 1 does not become sufficiently
better than primary CPICH 2.
Event 1J is a new criteria defined exclusively for HSUPA operations.
Best Cell Change
5-98
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Best Cell ChangeBest Cell ChangeThe UE sends a measurement report only when the difference of signal strengths is greater than a threshold (Hysteresis) for a predefined duration (Time to Trigger)
– event 1D: Change of Best Cell
CPICH 1
CPICH 2Hysteresis
Hysteresis
Reporting event 1D
Time
Measurementquantity
ΔTTime to Trigger
5-99
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The UE sends a measurement report triggered by event 1J when a cell that is exclusively in the DCH
active set becomes stronger than the weakest cell in the E-DCH Active Set. Simply put, this event
indicates transition of a cell from the R99 active set to the R99+R6 active set.
Event 1J is mainly used for managing the E-DCH active set when there is a difference in the members of
the two sets. In real operational scenarios we expect the DCH active set and E-DCH active set to be one
and the same. However, to further simplify HSUPA operations, it may be advantageous to have the
smallest possible active set size for the E-DCH to reduce processing power and hardware resource usage at
the UE and the Node B. As a result, there may be scenarios in which the E-DCH active set size is different
(less than) from the DCH active set size. In our example, CPICH P3 belongs only to the DCH active set,
so the DCH active set size is one greater than the E-DCH active set size. In such a case, event 1J can help
the network (RNC) decide when to replace P1 in the E-DCH active set with P3 from the DCH active set.
This mechanism guarantees that the best radio links in the DCH active set are also included in the E-DCH
active set when there is a difference between the two.
It may seem paradoxical that a downlink measurement procedure is used as the basis for making decisions
about which cells should be used for uplink radio links! Unfortunately, there are no mechanisms available
today for making uplink quality estimates on a per-radio-link basis in an effective and useful manner. The
uplink measurements at the Node B are a per Radio Link Set (RLS) and not per Radio Link (RL), which is
necessary to evaluate the quality of the uplink. In conclusion, the usefulness of this measurement is based
on the assumption of a symmetric radio-link quality in both uplink and downlink, which is valid in most
situations.
Event 1J for HSUPA
5-100
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Event 1J for HSUPAEvent 1J for HSUPA
P1
P2
Event 1J Time
Pilot Strength
P3
DCH Active set = {P1, P2, P3} E-DCH Active Set = {P1, P2}
E-DCH Active Set = {P3, P2}Triggered by event 1J
5-101
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This slide depicts the Intra Node B synchronized E-DCH cell handover message sequence. As shown in
the diagram, the UE contains the active set, which includes sectors 1, 2, and 3. The E-DCH serving RLS is
1 and 2 and the HSUPA-serving cell is sector 1. The word synchronized means that the activation time is
sent to the UE, which informs the UE about the time at which it should switch over to the target cell /
sector.
1. The need for a serving E-DCH cell change is decided by the SRNC. It thereby requests the serving
E-DCH S-NB to perform a synchronized radio link reconfiguration using the NBAP Synchronized
Radio Link Reconfiguration Prepare message. This message includes the E-DCH RL ID.
2. The serving E-DCH S-NB transmits an NBAP Radio Link Reconfiguration Ready message to the
SRNC. The parameters included in this message are the AGCH channelization code (and
scrambling code) and E-RNTI.
3. The SRNC now responds to the S-NB by transmitting the NBAP Radio Link Reconfiguration
Commit message, which includes the SRNC-selected activation time in the form of a CFN.
4. The Radio Bearer Reconfiguration message is then transmitted from the SRNC to the UE with
information parameters such as activation time, E-DCH information and the E-RNTI.
5. At the specified activation time, the UE now stops reception of E-DCH absolute grants from the
source E-DCH cell and starts reception of E-DCH absolute grants from the target E-DCH cell. It
thereby sends a Radio Bearer Reconfiguration Complete message to the SRNC in return.
Intra-Node B – Sync E-DCH Cell Change
5-102
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
IntraIntra--Node B Node B –– Sync ESync E--DCH Cell ChangeDCH Cell Change
S - NB1
SRNC
23Active Set Sectors 1, 2, 3
EDCH-Serving RLS is 1, 2HSUPA Serving Cell is 1
1. RL Reconfig. Prepare
2. RL Reconfig. Ready3. RL Reconfig. Commit
4. Radio Bearer Reconfiguration• Activation time, Serving E- DCH RL IND, EDCH Control Channel info• E-RNTI
5. Radio Bearer Reconfiguration Complete
Measurement Report
E-DCH best cell change to sector 2
5-103
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
This slide illustrates a synchronized inter Node B serving E-DCH cell change. As shown in the diagram,
the UE contains the active set, which includes sectors 1, 2, and 3. The E-DCH-serving RLS is 1 and 2 and
the E-DCH serving cell is sector 1, S-NB. The best cell change happens to T-NB, sector 1.
1. In this example, the source and target E-DCH cells are controlled by different Node Bs (i.e., S-NB
and T-NB). The SRNC decides there is a need for a serving E-DCH cell change. As a result, it
requests the source E-DCH S-NB to perform a synchronized radio link reconfiguration using the
NBAP Radio Link Reconfiguration Prepare message, which removes its E-DCH resources for the
source E-DCH radio link. This message includes information parameters such as E-DCH MAC-d
flows to delete.
2. The source E-DCH S-NB responds by sending an NBAP Radio Link Reconfiguration Ready
message to the SRNC, which includes no E-DCH related parameters.
3. The SRNC sends a Radio Link Reconfiguration Prepare Requests message to the target E-DCH T-
NB to perform a synchronized radio link reconfiguration.
Using the NBAP message, which adds E-DCH resources for the T-NB radio link, this message
includes E-DCH FDD information, a DRNC-selected E-RNTI and the E-DCH RL ID.
4. The target E-DCH T-NB responds with the NBAP Radio Link Reconfiguration Ready message in
return to the SRNC, which contains the E-DCH FDD information response.
5. Initiated by the SRNC, the new Iub Data transport bearers are set up using the ALCAP protocol.
This request includes the AAL2 binding identity to bind the Iub data transport bearer to the E-
DCH.
6. The SRNC transmits the NBAP Radio Link Reconfiguration Commit message to the source E-
DCH S-NB, which includes the activation time. At the activation time, the source E-DCH S-NB
stops and the target E-DCH T-NB starts transmitting on the E-DCH to the UE. This message
includes the SRNC-selected activation time in form of a CFN.
Inter-Node B – Sync Serving E-DCH Cell Change
5-104
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
InterInter--Node B Node B –– Sync Serving ESync Serving E--DCH Cell DCH Cell ChangeChange
S - NB1
SRNC
23Active Set Sectors 1, 2, 3E-DCH Serving RLS 1, 2HSUPA Serving Cell is (1, S-NB)
1. RL Reconfig. Prepare
T - NB1
2. RL Reconfiguration Ready
6. RL Reconfiguration Commit
3. RL Reconfig Prepare
4. RL Reconfig Ready
Active set sectors 1, 2, 3E-DCH non-serving RLS 1, 2
23
5. ALCAP Iub Data Trans. Bearer Setup
5-105
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
7. The SRNC transmits the NBAP Radio Link Reconfiguration Commit message to the target E-
DCH T-NB, which consists of the activation time. At the indicated activation time, the source E-
DCH S-NB stops, and the target E-DCH Node B starts transmitting on the E-DCH to the UE. It
includes the SRNC selected activation time in the form of a CFN.
8. The SRNC then transmits the Radio Resource Control (RRC) Radio Bearer Reconfiguration
message to the UE. This includes information parameters such as activation time, E-DCH
information and the E-RNTI.
9. At the indicated activation time, the UE stops receiving the E-DCH in the source E-DCH cell and
starts E-DCH reception in the target E-DCH cell. The UE thus responds and returns a RRC Radio
Bearer Reconfiguration Complete message to the SRNC.
10. If the new Iub data transport bearer was set up in step 5, the SRNC initiates release of the old Iub
data transport bearer using the ALCAP protocol.
Inter-Node B – Sync Serving E-DCH Cell Change
5-106
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
InterInter--Node B Node B –– Sync Serving ESync Serving E--DCH DCH Cell ChangeCell ChangeS - NB
1
SRNC
.
23Active Set Sectors 1, 2, 3E-DCH Serving RLS 1, 2HSUPA Serving Cell is (1, S-NB)
8. Radio Bearer Reconfiguration
T - NB1
9. Radio Bearer Reconfiguration Comp.
Active Set Sectors 1, 2, 3E-DCH Non-Serving RLS 1, 2
23
7. RL Reconfig. Commit
10. ALCAP Iub Data Trans. Bearer Release
5-107
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
The data that the Node B receives on the uplink E-DCH must be transported to the RNC for possible
selection combining with other data blocks (when macro-diversity is used) and subsequently transmitted to
the packet core network. The transport of user data between the Node B and the RNC is done over the Iub
interface on the user plane of the Iub protocol stack. The user plane utilizes the Frame Protocol (FP), and
the diagram in this chart outlines the structure of the E-DCH Data FP.
Each MAC-es PDU that is received by the Node B is disassembled into MAC-d flows and sent on separate
transport bearers to the RNC. The FP normally sends data frames on the uplink and downlink every TTI,
i.e. transmission time interval (10, 20, 40 or 80 ms). HSUPA efficiency may be increased in the case of a
2ms TTI by bundling subframes into one E-DCH frame and sending the E-DCH frames every 10 ms, for
example.
Here we see the generic format for the E-DCH data frame. Each frame is divided into a Header and
Payload part. The Header carries the frame type (control or data), a cyclic redundancy check (CRC) for the
header portion, a frame sequence number (FSN) which counts the frame itself as well as a Connection
Frame Number (CFN) that indicates when this MAC-e PDU was decoded at the physical layer. The
remainder of the header carries MAC-es specific info like the Data Description Indicator (DDI), which is a
mapping to MAC-d flow ID and size, the number of MAC-es PDUs, the number of HARQ
retransmissions and the number of MAC-d PDUs (all for each subframe). All this information is necessary
for the correct demultiplexing of the frames at the RNC and their subsequent delivery to the higher layers.
For a 2 ms TTI, a maximum of 5 subframes can exist and the subframe number ranges from 0 to 4.
The payload is a concatenation of MAC-es PDUs for each subframe. Thus, the first MAC-es PDU of the
first subframe is followed by the second MAC-es PDU of the first subframe, etc. until the last MAC-es
PDU of the last subframe. There is also the possibility of attaching an optional 16-bit Payload CRC field
that applies to the entire payload.
E-DCH Data Frame
5-108
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
EE--DCH Data FrameDCH Data Frame
DDI1 … DDI n
FT: Frame Type
Payload CRC
1st Subframe info
Subframe 1 Payload
Frame Sequence Number
Connection Frame Number
Header CRC FT
Last Subframe info
Hea
der
Payl
oad
Number of MAC-es PDUs
Number of HARQ Retransmissions
Number of MAC-d PDUs
Last Subframe Payload
MAC-es PDUs 1st to last Subframe
Optional
5-109
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
During HSUPA operations, the UE is often in soft handover with more than on cell, thus using the same
benefits of macro-diversity that exist in R99. Since the responsibility of retransmitting erroneous transport
blocks is now at the Node B and not the RNC, The UE must decode the individual acknowledgments on a
downlink feedback channel (E-HICH) from each and every cell that it is communicating with. A single
positive acknowledgment (ACK) from any one of the cells in its E-DCH active set is enough for the UE to
proceed with subsequent Hybrid ARQ transmissions. The Serving E-DCH cell is the one with the overall
responsibility with regards to scheduling and grant of uplink radio resources to the UE. This cell is usually
the cell with the best radio conditions (and is the serving HSDPA cell as well in the likely case when
HSDPA is used simultaneously).
When the Serving E-DCH cell fails to receive an uplink E-DCH payload (MAC-e PDU), unlike the other
cells in the active set, it must report that failure to the RNC. It will do so if the decoding fails after the
maximum number of retransmissions have been reached and the Retransmission Sequence Number (RSN)
indicates that the UE has started with a new payload (RSN=0). In that case, at least one of the other cells in
the active set must have succeeded in decoding the previously sent data. At this point, the serving cell
sends a HARQ failure indication to the RNC. This is done by setting the ‘Number of MAC-es PDUs’ field
to zero and sending the true number of retransmissions that occurred for the failed payload. The HARQ
failure indication helps the RNC in doing the selection-combining better, and is also an indirect measure of
how well the serving E-DCH cell is performing compared to the other cells in the uplink.
HARQ Failure Indication
5-110
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
HARQ Failure IndicationHARQ Failure Indication
RNC
ACK
NACK
RSN=0RSN=0
RSN=0NACK
RSN=0
Data Frame
HARQ Failure Ind.
No data transmission
or failure indication
Serving E-DCH Cell
5-111
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Summary
5-112
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
SummarySummary• RRC establishment procedures have been enhanced to
indicate the E-DCH capability of the UE • Radio Link (NBAP), Radio Bearer Setup (RRC) and Radio
Bearer Reconfiguration procedures have been enhanced to assign HSUPA logical, transport and physical channel parameters to the UE
• SRNC configures the Node B and UE with QoS Parameters for E-TFC selection at the UE and scheduling of grants at the Node B
• The UE transmits scheduling info and / or Happy Bit for request for grants from the Node B
• Based on assigned grants, logical channel priority, buffer status and HARQ profile, the UE selects the best possible transport block to be transmitted
• Whenever an E-DCH best cell change occurs, intra-Node B and inter-Node B handovers are possible
5-113
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Review Questions
5-114
Mastering HSDPA/HSUPA Signaling
HSUPA Data Call Setup
Review QuestionsReview Questions1. Which message carries the E-DCH physical layer
capability?2. What is the significance of assigning primary and
secondary E-RNTIs and when are they used? What messages signal these values to the UE?
3. What is the E-DCH MAC-d flow?4. What is the DDI? What are the parameters that are
mapped to the DDI at the Node B and UE? How are they signaled to the Node B and UE?
5. What parameters trigger the UE to request scheduled grants and how are they sent?
6. What is the difference between synchronous and un-synchronous cell change procedures?
5-115
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
MultiMulti--Services Services ScenarioScenario
6-1
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Objectives
6-2
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
ObjectivesObjectivesAfter completing this module, you will be able to:
• Describe the Multi-RAB / Multi-Services scenario of AMR/HSDPA/HSUPA
• Step through the call flow for– AMR/HSDPA– AMR/HSUPA
• Draw the end-to-end call of Multi-Services that includes AMR voice, HSDPA and HSUPA data calls
6-3
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
It is assumed that the UE is already registered with the Core Network (CN). When a user starts to browse a
website, an HSDPA call is set up. This slide illustrates RRC connection establishment for the start of the
HSDPA session.
• The UE initiates an RRC connection by sending an RRC Connection Request on the CCCH to the
RNC. This message contains the UE identity and the establishment cause is a high priority
signaling call.
• The RNC allocates a U-RNTI and an H-RNTI that uniquely identify the UE in the system. These
identities are sent in the RRC Connection Setup message (on the DL- CCCH).
• The UE acknowledges the RNC by transmitting a RRC Connection Setup Complete message.
RRC Connection Establishment for HSDPA
6-4
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
RRC Connection Establishment for RRC Connection Establishment for HSDPAHSDPA
UE
RNC PS-CN
RRC Connection Request
RRC Connection Setup
RRC Connection Setup Complete
Establishing a Web browsing session
6-5
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
• The required service request is sent by the UE to the RNC in an Initial DT (Service Request)
message that mentions the type of service. In our example, the type of service is signaling.
• The RNC forwards the service request to the SGSN by transmitting the Connection Request
message, and piggybacks the Initial UE Message to the SGSN, which carries the previously
mentioned Service Request CR [IUM (service request)]. It also sends the Iu-signaling link identity.
• The SGSN may invoke the security procedures for authentication, ciphering and integrity check at
this point.
• Either at the end of or absence of security procedures, the upper layer in the UE sends a request to
the CN to set up the data session. The UE requests the desired QoS by sending a direct transfer
RRC UL DT (Activate PDP CTX Req.) message to the RNC. It contains parameters such as APN,
PDP address attributes, and all the necessary QoS characteristics.
• The RNC forwards the request by sending the DT (Activate PDP Context) (a NAS message) using
the initial UE RANAP message to the SGSN on the GTP-C link.
• The SGSN transmits the Create PDP Context Request to the GGSN in a “handshake” procedure to
negotiate the requested QoS and create a GTP-U tunnel. The tunnel is identified by the Tunnel End
Point IDs (TEID).
Setting Up an HSDPA Call
6-6
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Setting Up an HSDPA Call Setting Up an HSDPA Call UE
RNC SGSN
Initial DT (Service Request) CR [IUM (Service Request)]
Security Procedures
GGSN
UL DT (Activate PDP CTX Req.) DT
(Act. PDP CTX Req.) Create PDPCTX Req.
Create PDPCTX Res.
6-7
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
• After negotiation of QoS in the Core Network (CN) (i.e., between the SGSN and GGSN) the
SGSN sends the RANAP RAB Assignment Request message over the Iu Interface to the RNC.
This message indicates in specific terms the QoS with several attributes such as throughput, delays,
error rate, RAB ID, etc.
• The RNC sends an NBAP RL Setup Request message to the Node B to set up a radio link to carry
the traffic for the UE with the desired QoS. It includes Mac-d flows needed, the HS-DSCH
physical layer category and CQI parameters.
• An appropriate radio link is set up by the Node B, which responds to the RNC with the NBAP RL
Setup Response message. This message includes HS-SCCH control information.
• To assign the required radio channels to support high speed data, the RNC sends the RRC Radio
Bearer Setup message to the UE. It includes Mac-d flows to add HS-DSCH information, H-RNTI
and U-RNTI.
• The UE thus acquires a new radio link and sends the RB Setup Complete message in return to the
RNC.
• The RNC further notifies the CN by sending the RANAP RAB Assignment Response message
indicating that radio resources are set up for the UE. The radio bearer for negotiated QoS has been
set up now.
• The PDP context establishment is finally completed by the GGSN and SGSN by sending the DT
PDP Context Accept message to the RNC.
• The RNC forwards the DL DT PDP Context Accept message to the UE. The UE now has an IP
address associated with the APN and itself.
The Web browsing session is now activated.
Radio Bearer for HSDPA
6-8
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Radio Bearer for HSDPARadio Bearer for HSDPAUE
RNC SGSNNode B1 RAB
Assignment Req.
Radio Bearer Setup
RB Setup Complete RAB AssignmentRes.
DT PDP CNXT Acc.DL DT PDP CNTXT Accept
Web Browsing Session Active
RL Setup Request
RL Setup Resp.
6-9
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
In this scenario of high-speed data service, the following channels exist over the air:
• High-speed user data is carried in the downlink on the HS-DSCH along with the HS-SCCH
control information.
• User data at R99 rates are carried in the uplink on the DPDCH along with signaling.
• To support high-speed user data in the downlink, the uplink also contains the HS-DPCCH for CQI
and ACK/NACK signaling.
• The downlink contains the DPCCH to cater to the TFC and power control information. Power
control is done only for data transmission on the uplink by the DL DPCCH. HS-DPCCH power
now depends on the power offset with respect to the UL DPCCH.
Channels Used for an HSDPA Call
6-10
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Channels Used for an HSDPA CallChannels Used for an HSDPA Call
DPCCH (TFCI, Pilot and Power Control)
HS-SCCH/HS-DSCH (Control/Data and Signaling)
HS-DPCCH (CQI and ACK/NACK)
DPDCH ( Data and Signaling)
6-11
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
In our scenario described earlier, a user makes a call to a friend to describe her trip to Europe. The
example illustrates signaling messages to establish an AMR call.
1. To set up a call, the UE sends the Initial Direct Transfer (Service Request) message to the RNC.
2. The RNC chooses the required CN and forwards the CR [IUM (service request)] (NAS message)
using the initial UE RANAP message to the MSC.
3. The CN may start with Security procedures that consist of the RANAP Security Mode Command
message to the RNC to start ciphering of a radio link for the UE.
4. The UE sends a NAS UL DT Setup message that includes the dialed digits of the desired
destination for the CN using a Direct Transfer RRC message.
5. The RNC then transparently forwards the NAS DT Setup message to the CN using the RANAP
Direct Transfer message.
6. The CN then sends the DT Call Proceeding message to the RNC.
7. The RNC passes the DL DT Call Proceeding message to the UE.
8. To set up the Radio Access Bearer (RAB) to carry the desired QoS for AMR voice, the CN sends
a RAB Assignment Request message to the RNC.
9. To assign the radio channels, the RNC sends the RRC Radio Bearer Setup message to the UE,
which consists of RAB information and UL and DL channelization codes.
10. The UE acquires a new radio link, and sends the Radio Bearer Setup Complete message back to
the RNC.
11. The RNC sends the Radio Bearer Reconfiguration message to the UE since some of the RLC
relevant parameters needed to be modified and reconfigured at the UE.
12. After required modification in the RLC parameters, the UE sends the Radio Bearer
Reconfiguration Complete message to the RNC.
Establishment of an AMR Call
6-12
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Establishment of an AMR CallEstablishment of an AMR CallUE
RNC MSC
Initial DT (Service Request)CR [IUM (Service Request)]
Security ProceduresUL DT Setup DT Setup
DT Call ProceedingDL DT Call ProceedingRAB Assignment RequestRadio Bearer Setup
Radio Bearer Setup Complete
RAB Assignment ResponseDT AlertingDL DT Alerting
UL DT Connect DT ConnectDT Connect AcknowledgeDL DT Connect Acknowledge
Radio Bearer ReconfigurationRadio Bearer Reconfiguration Comp.
Initiating a voice (AMR) call
6-13
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
The functions of the Radio Bearer Setup message and Radio Bearer Reconfiguration message can be
combined into a single Radio Bearer Reconfiguration message in specific implementations.
1. The RNC sends a RANAP RAB Assignment Response message to the MSC indicating that radio
resources are set up for the UE.
2. The MSC sends the DT Alerting message to the RNC indicating that the called party is being
alerted by a ring tone.
3. The RNC forwards this information to the UE by sending a UL DT Alerting message.
4. When the called party answers, the MSC completes the connection by sending a DT Connect
message to the RNC.
5. The RNC transmits this indication by sending a UL DT Connect message to the UE.
6. The UE in response sends the DL DT Connect Acknowledge message to the MSC.
7. The RNC transmits a DT Connect Acknowledgement message to the MSC.
The user is now talking to her friend using the established AMR call.
Establishment of an AMR Call (continued)
6-14
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Establishment of an AMR CallEstablishment of an AMR Call (continued)(continued)UE
RNC MSC
Initial DT (Service Request)CR [IUM (Service Request)]
Security ProceduresUL DT Setup DT Setup
DT Call ProceedingDL DT Call ProceedingRAB Assignment RequestRadio Bearer Setup
Radio Bearer Setup Complete
RAB Assignment ResponseDT AlertingDL DT Alerting
UL DT Connect DT ConnectDT Connect AcknowledgeDL DT Connect Acknowledge
Radio Bearer ReconfigurationRadio Bearer Reconfiguration Comp.
Initiating a voice (AMR) call
6-15
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
In this scenario of simultaneous high-speed data and voice, the following channels exist over the air.
• High-speed user data is carried in the downlink on the HS-DSCH along with the HS-SCCH for
control information.
• User data at R99 speed is carried in the uplink on the DPDCH, which may also carry user voice
and signaling.
• To support high-speed user data in the downlink, the uplink also contains the HS-DPCCH for
CQI/ACK signaling.
• Additionally, user voice and associated signaling are carried on the DPDCH in the uplink and
downlink.
• Both uplink and downlink have to contain the DPCCH to cater to TFC and power control
information. Power control is done only for voice on the downlink by the UL DPCCH, but for both
voice and data on the uplink by the DL DPCCH.
Channels Used for an HSDPA/Voice Call
6-16
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Channels Used for an HSDPA/Voice CallChannels Used for an HSDPA/Voice Call
Multi-RAB Configuration
DPCCH (TFCI, Pilot and Power Control)
HS-SCCH/HS-DSCH (Control/Data and Signaling)
DPDCH (Voice and Signaling)
DPCCH (TFCI, Pilot and Power Control)
HS-DPCCH (CQI and ACK/NACK)
DPDCH (Voice, Data and Signaling)
6-17
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Suzanne decides to upload the photographs of her tour in Europe for her friend to view. She composes an
email message with the photographs and sends it to her friend’s email address.
The UE triggers a Direct Transfer Service Request message with the appropriate PDP context status for
the email service. This example illustrates the use of the same APN for both HSDPA and HSUPA, and
uses the same QoS. This Direct Transfer message is forwarded by the RNC to the SGSN on the Iu-PS
signaling link. This may result in invoking security procedures for HSUPA service.
Addition of an HSUPA-to- HSDPA/AMR Call
6-18
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Addition of an HSUPAAddition of an HSUPA--toto-- HSDPA/AMR HSDPA/AMR Call Call
UE
RNC
Initial DT(Service Request)
CR [IUM (Service Request)]
Security Procedures
AMR call and web browsing
is ongoing
Starts uploading data
SGSN GGSN
6-19
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
1. After negotiation in the Core Network (CN) (i.e., between the SGSN and GGSN), the SGSN
sends the RANAP RAB Assignment Request message over the Iu Interface to the RNC. This
message indicates in specific terms the QoS by data rate, delay, acceptable error rate, etc.
2. The RNC sends an NBAP RL Setup Request message to the Node B to set up a radio link to carry
the traffic for the UE with the desired E-DCH MAC-d flow ID(s).
3. An appropriate radio link is thereby setup by the Node B that responds to the RNC with the
NBAP RL Setup Response message. To assign the required radio channels to support high-speed
data, the RNC sends the RRC Radio Bearer Setup message to the UE. It contain all UL and DL E-
DCH channelization codes and signature sequences.
4. The UE thus acquires a new radio link and sends the RB setup Complete message in return to the
RNC. The RNC further notifies the CN by sending the RANAP RAB Assignment Response
message indicating that radio resources are set up for the UE. The CN and the UE may now
exchange traffic.
Adding an HSUPA to an Existing HSDPA/AMR Call
6-20
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Adding an HSUPA to an Existing Adding an HSUPA to an Existing HSDPA/AMR CallHSDPA/AMR Call
UE
RNC SGSNNode B1
RAB Assignment Req
RL setup Request
RL setup Response
Radio Bearer Setup
RB setup Complete
RAB Assignment Response
AMR voice call and uploading photos is active, Web browsing in standby state
ServingCell sector 1Sector 1,2,3 E-DCHActive set and servingRLS
2 3
Radio Bearer ReconfigurationRadio Bearer Reconfiguration Comp.
6-21
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
In this scenario of simultaneous high-speed data and voice, the following channels exist over the air:
• High-speed user data is carried in the uplink on the E-DPDCH along with E-DPCCH for control
information.
• The CQI, ACK/NACK information in the uplink is carried on the high-speed HS-DPCCH.
• In the downlink, high-speed user data is carried on the HS-DSCH and control information is carried
on the HS-SCCH.
• To support high-speed user data in the uplink, the downlink also contains the E-AGCH, E-RGCH
and E-HICH.
• Additionally, user voice along with associated signaling is carried on the DPDCH in the downlink
as well as the uplink.
• Both the uplink and downlink have to contain the DPCCH to cater for TFC and power control
information. Power control is done only for voice on the downlink by the uplink DPCCH. For both
voice and data on the uplink, the downlink DPCCH is used.
Simultaneous HSDPA, HSUPA and Voice
6-22
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Simultaneous HSDPA, HSUPA and VoiceSimultaneous HSDPA, HSUPA and VoiceMulti-RAB Configuration
DPCCH (TFCI, Pilot and Power Control)
HS-SCCH, HS-DSCH (High Speed Data)
DPDCH (Voice and Signaling)
DPCCH (TFCI, Pilot and Power Control)
HS-DPCCH (CQI and ACK/NACK)
DPDCH (Voice and Data, Signaling)
E-DPDCH,E-DPCCH (Data and Control Info.)
E-AGCH,E-RGCH (Absolute and Relative Grants)
E-HICH (ACK and NACK)
6-23
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
The user, Suzanne, has finished uploading the photo files. This slide illustrates the procedure for HSUPA
call release on detecting inactivity for HSUPA service.
1. To release the radio access bearer with the negotiated QoS, the SGSN sends the RAB Assignment
Request (Release) to the RNC.
2. The RNC sends the Radio Link Reconfiguration Prepare message to the Node B. The message
includes E-DCH information parameters to be deleted such as E-DCH MAC-d flows, logical
channel IDs, and E-DCH radio links.
3. The Node B informs the RNC that it is ready for RL reconfiguration by sending the RL
Reconfiguration Ready message. The message includes the E-DPDCH, E-AGCH, E-RGCH and
E-HICH channel deletion information for each radio Link.
4. The RNC then sends an RL Reconfiguration Commit message to the Node B. Now, the old radio
link is released. On receiving this message, the Node B switches to the new configuration at the
next coming CFN with a value equal to the value requested by the RNC in the CFN IE.
5. The RNC forwards the Radio Bearer Release message to the UE. The RNC instructs the UE to
delete all E-DCH MAC-d flows, etc.
6. The UE responds to the RNC with the Radio Bearer Release Complete.
7. The RNC sends a Radio Bearer Reconfiguration message to the UE since some of the RLC
relevant parameters need to be modified and reconfigured at the UE.
8. After required modification in the RLC parameters, the UE sends a Radio Bearer Reconfiguration
Complete message to the RNC.
9. Finally The RRC connection pertaining to HSUPA control plane is released both on Iu and RRC
Now the user continues with the ongoing call to her friend and the Web browsing session.
Release of an HSUPA Call
6-24
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Release of an HSUPA CallRelease of an HSUPA CallUE
RNC
RAB assign. Req( Release)
Radio Bearer Release
Radio Bearer Release Complete
SGSN
AMR voice call, web browsing session continues and uploading photos is in standby state
Radio Bearer Reconfiguration
Radio Bearer Reconfig. CompleteRAB Assignment
Response (Released)
Node B1
RL Reconfig. Prepare
RL Reconfig. Ready
RL Reconfig. Commit
Uploading is completed
SGSN
Signaling Connection Release RLSDRLC
6-25
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
The user now wants to close the call with her friend. This slide depicts the signaling messages used to
release the AMR call.
1. The UE initiates the procedure by sending a UL Direct Transfer (Disconnect) (call control NAS
message) indicating the normal clearing of the call.
2. The RNC further transmits this to the MSC by sending a DT (Disconnect) message.
3. The MSC transmits a Direct Transfer Release to the RNC
4. The RNC transmits this message by sending a Direct Transfer (Release) to the UE. Now the UE
and MSC have released the direst transfer transaction between NAS CC peer layers.
5. The UE responds with the Uplink Direct Transfer (Release complete), indicating the release of the
AMR call.
6. The RNC forwards the DT (Release Complete) message to the MSC.
7. The MSC initiates the procedure by sending the RLSD to release the SCCP connection.
8. The RNC sends a Signaling Connection Release to release the RRC control plane pertaining to the
AMR call.
9. The RNC finally sends an RLC message to the MSC indicating release of all resources pertaining
to the AMR call
Now the user continues browsing the website.
Release of an AMR Call
6-26
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Release of an AMR CallRelease of an AMR CallUE
RNC MSC
6. DT (Release Complete)
Only Web browsing session continuesand uploading photos is in standby state
1. UL Direct Transfer (Disconnect)2. DT (Disconnect)
3. DT (Release)4. DL Direct Transfer (Release)
5. UL DT (Release Complete)
Terminating a voice call
7. RLSD8. Signaling Connection (Release)9. RLC
6-27
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
She finally also wants to close the Web browsing session.
The slide depicts the signaling messages involved in releasing the HSDPA call.
1. The UE sends a UL DT Deactivate PDP CTX Request to the RNC to deactivate the negotiated
QoS, which includes the APN, IP Address and QoS type.
2. The RNC transmits this transparently by sending a DT (Deactivate PDP Context Request) to the
SGSN.
3. The SGSN sends a Delete PDP Context Request to the GGSN.
4. The GGSN responds with a Delete PDP context Response to the SGSN. As a result, the tunnel for
the UE ID is deleted
5. To release the radio access bearer and negotiated QoS, the SGSN sends a RAB Assignment
(Release) Request to the RNC.
6. The RNC sends a Radio Bearer Release message to the UE .The parameters carried include HS-
DSCH MAC-d flows to delete and the RABS to be removed
7. The UE responds to the RNC with a Radio Bearer Release Complete.
8. The RNC responds to the SGSN with a RAB Assignment (Release) Response message.
9. The SGSN indicates the deactivation of QoS to the RNC by sending a DT (Deactivate PDP
Context Accept).
10. The RNC transmits a DL DT (Deactivate PDP Context Accept ) message to the UE indicating the
deactivation of the QoS is complete.
Release of an HSDPA Call
6-28
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Release of an HSDPA CallRelease of an HSDPA CallUE
RNC
UL DT (Deactivate PDP CTX Req.)DT (Deact. PDPCTX Request) Delete PDP
CTX Request
Delete PDP CTX Res.RAB Assignment (Rel.)
RequestRadio Bearer Release
Radio Bearer Release Complete
DT (DeAct. PDP CTX Accept)
DL DT(Deactivate PDP CTX Accept)
Web browsing session closed
RAB Assignment (Release) Resp.
RRC Connection Release Request
RRC Connection Rel. Complete
Iu Release
SGSN GGSN
6-29
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
The Web browsing session is deactivated:
1. The SGSN initiates the procedure by sending an Iu Release Command to release the Iu connection
and all UTRAN resources related only to that Iu connection. The procedure uses connection-
oriented signaling.
2. The RNC finally sends an Iu Release Complete message to the SGSN indicating release of all
resources.
3. The RNC sends an RRC Connection Release Request to the UE to release the SRB.
4. The UE responds with an RRC Connection Release Complete to the RNC.
The UE is now in idle state.
Release of an HSDPA Call (continued)
6-30
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Release of an HSDPA Call Release of an HSDPA Call (continued)(continued)UE
RNC
UL DT (Deactivate PDP CTX Req.)DT (Deact. PDPCTX Request) Delete PDP
CTX Request
Delete PDP CTX Res.RAB Assignment (Rel.)
RequestRadio Bearer Release
Radio Bearer Release Complete
DT (DeAct. PDP CTX Accept)
DL DT(Deactivate PDP CTX Accept)
Web browsing session closed
RAB Assignment (Release) Resp.
RRC Connection Release Request
RRC Connection Rel. Complete
Iu Release
SGSN GGSN
6-31
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Summary
6-32
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
SummarySummary• Several scenarios of R99, R5 and R6 multi-
services can be handled together• An AMR call can be added to an existing
HSDPA service and vice versa• An HSUPA service can be added to an
existing AMR call while HSDPA service is in standby state
• Once the HSDPA service resumes, it can be added to an existing HSUPA and AMR call, making it possible for all services to coexist
6-33
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Review Questions
6-34
Mastering HSDPA/HSUPA Signaling
Multi-Services Scenario
Review QuestionsReview Questions
1. When can the UE and network go to standby state? What is the effect?
2. What is the effect of Radio Bearer Reconfiguration?
3. When the RRC connection is released, does the PDP context still exist?
4. Can a Radio Bearer Release message reconfigure a particular service while releasing another service?
6-35
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
HSPA InterworkingHSPA Interworking
7-1
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Objectives
7-2
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
ObjectivesObjectivesAfter completing this module, you will be able to:
• Describe the need for an R5/R6-to-R99 handover and list the processes and parameters required for supporting the handover
• Describe the processes and step through the end-to-end message flow for Inter-RAT handovers between HSPA and GPRS/EDGE
• Describe the processes and step through the end-to-end message flow for Inter-RAT handovers between GPRS/EDGE and HSPA
7-3
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
This slide illustrates an example of R5- to-R99 handovers. As shown in this diagram, cell 1 in Node B1
and cell 1 and 2 in Node B2 are part of the active set. The UE is on a voice call served by cell, Node B1
and cell 1 and cell 2 in Node B2. The UE is in soft handover with these cells. The best HS-DSCH serving
cell is cell 1, which is part of cell 1 in Node B2. Node B1 does not support R5.
The UE continuously monitors the active set cells and other neighboring cells and measures their pilot
strength. The UE, while monitoring the active set, notices that cell 1 in Node B1 is received stronger than
the current serving cell 1 in Node B2. The UE transmits a Measurement Report message on the DPCCH to
the RNC. The message contains intra-frequency measurement results, triggered by the event 1D "change
of best cell.” The RNC must decide whether to switch to cell 1 in Node B1 that supports only R99, and
initiate a Radio Bearer Reconfiguration.
The situation of going from R5 to R99 is rare (only at the borders). So, the RNC determines that the UE is
clearly going away from the HSDPA coverage area, and triggers a Radio Bearer Reconfiguration and hand
down to R99.
R5-to-R99 Handovers (Initial)
7-4
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
R5R5--toto--R99 R99 HandoversHandovers (Initial)(Initial)
UE
Serving Cell - cell 1DPCH
HS-SCCH/HS-PDSCH
HS-DPCCH/DPDCH/DPCCH
DPDCH/DPCCH
DPCHNo support of R5/HSDPA
Best Cell change event 1D is triggered to cell 1 in Node B1 butNode B1 does not support HSDPA
After best cell change to cell 1 in Node B1,UE has been reconfigured
by Node B1 from HSDPA to R99 data call
The UE is on a voice call with Node B1, cell 1 and Node B2 cell 1 and cell2 (soft handover) and HSDPA call with Node B2, cell 1 (serving cell)
High-Speed control/data
CQI, ACK/NACK / Pilot,TPC, Voice and Sig
Voice, Signaling, TPC, Pilot
Voice, Signaling, TPC, Pilot
Voice, Signaling, Data, Pilot, TPC
Node B12
1
3Node B2
213
Active set cells cell 1
Active set cells cell 1, and cell2
7-5
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
This example summarizes the R5-to-R99 handover signaling messages.
As shown in the figure, the UE is in cell 1 of the HSDPA serving cell with source Node B2.
1. The UE transmits a Measurement Report message containing intra-frequency measurement results
(here assumed to be triggered by the event 1D “Change of Best Cell“).
2. The SRNC performs the best cell change on cell 1in Node B1, which supports only R99.
3. The SRNC sends a synchronized Radio Link Reconfiguration Prepare message to the source Node
B. Parameters that are sent mainly include HS-DSCH MAC-d Flows to Delete.
4. The source Node B2 responds with the Radio Link Reconfiguration Ready.
5. The SRNC sends a Radio Link Reconfiguration Prepare message to the target Node B1 asking it
to perform a synchronized radio link reconfiguration. Parameters include RAB reconfiguration
information, UL and DL transport channels to be configured, RLC parameters to be modified,
DCH information like DPDCH /DPCCH codes, and scrambling codes on the UL and DL
scrambling code.
6. The target Node B1 informs the SRNC that it is ready for RL reconfiguration by sending a Radio
Link Reconfiguration Ready message to the SRNC. Parameters include DCH information.
7. The SRNC initiates a setup of new Iub Data Transport Bearers using the ALCAP protocol. This
request contains the AAL2 binding identity to bind the Iub data transport bearer to the DCH.
R5-to-R99 Handovers (Prepare)
7-6
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
R5R5--toto--R99 R99 HandoversHandovers (Prepare)(Prepare)Node B2
1
SRNC
2. Decision for best cell change to cell 1,Node B1(only R99 support)
23
HSDPA Serving cell is (Cell 1, Node B2)1. Measurement Report (event 1D)
Node B11
7. Iub bearer - DCH
3. RL Reconfiguration Prepare
4. RL Reconfiguration Ready
5. RL Reconfig Prepare
6. RL Reconfig Ready
7-7
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
8. The SRNC transmits the NBAP Radio Link Reconfiguration Commit message to the source Node
B2. Parameters include activation time in the form of a CFN. At the indicated activation time, the
source HS-DSCH Node B2 stops and the target DCH Node B1 starts transmitting on the DCH to
the UE.
9. The SRNC now transmits a Radio Link Reconfiguration Commit to the target Node B1 including
the activation time. Parameters include selected activation time in the form of a CFN.
10 SRNC now sends a Radio Bearer Reconfiguration to the UE. Parameters include activation time,
DCH information, transport channel information, RLC parameters logical channel identifiers with
priorities, and the new U-RNTI, if required.
11. On successful radio bearer reconfiguration, the UE sends a Radio Bearer Reconfiguration
Complete message to the SRNC. Now, the target cell starts DCH transmission and the source cell
stops HS-DSCH transmission.
12. Now, the SRNC initiates release of the old Iub data HS-DSCH transport bearer using the ALCAP
protocol.
R5-to-R99 Handovers (Prepare)
7-8
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
R5R5--toto--R99 HandoversR99 Handovers (Prepare)(Prepare)NodeB2
1SRNC
.
23
9. RL Reconfig Commit
Node B11
10. Radio Bearer Reconfiguration
11. Radio Bearer Reconfiguration Complete
12. Iub Bearer HS-DSCH Release
8. RL Reconfiguration Commit
7-9
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
We have already seen that how the UE switches from the R5 serving cell to the R99 serving cell. This
slide gives the overview of changes / reconfigurations required after switching to an R99 cell that is from
a R5 data call to an R99 data call.
Now cell 1 in Node B1 becomes the serving cell for the UE, which is an R99 serving cell. Nevertheless,
the UE is now reconfigured to a R99 data call from an R5 data call. Since the UE is in soft handover
between cell 1 in Node B1 and cells 2 and 3 in Node B2, the reconfigured data call and voice call is
handled by both Node Bs. On both the UL and DL in active set cells of both Node Bs, the UE is on a
voice call. The UE is on a data call on the DL in active set cells of both Node Bs. The channels used for
transmission and reception are DPCH in the downlink and DPDCH/DPCCH in the uplink for both Node
Bs. The signaling, power control commands, pilot preamble and TFCI are sent on the UL, and the DL.HS-
PDSCH link between the UE and cell 1 in Node B2 is deleted after reconfiguration.
R5-to-R99 Handovers (Final)
7-10
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
R5R5--toto--R99 HandoversR99 Handovers (Final)(Final)
UE
DPCH
DPDCH/DPCCH
DPDCH/DPCCH
DPCH
After Reconfiguration
R99 data and voice call
HSDPA link is deleted and voice call /
R99 Data call continues
Voice, signaling/TPC, Pilot, TFCI
Voice, Data, Signaling /TPC,Pilot, TFCIVoice, Sig / TPC, Pilot, TFCI
Voice, Data, Sig /TPC, Pilot, TFCI
Node B12
1
Serving cell-cell 1
3
Node B22
1
3
Active Set cells cell 1
Active Set cells cell 1,
and cell2
7-11
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
This diagram shows the reason for handovers between R6 and regular R99 networks with their associated
channels.
Cell 1 in Node B1, cell 1 in Node B2 and cell 1 in Node B3 are in active sets. Cell 1 in Node B1 and cell 1
in NodeB2 belong to the E-DCH active set. Cell in Node B1 is the E-DCH serving cell and cell 1 in Node
B2 is part of the non-serving RLS. Cell 1 in Node B3 supports only R99. This scenario depicts the 3-way
soft handover of the UE between cell 1 in Node B1, cell 1 in Node B2 and cell 1 in Node B3 for voice
calls, and the E-DCH uplink transmission by the UE to cell 1 in Node B1 and cell 1 in Node B2. The UE
monitors all pilots in active sets and measures their pilot strength. It happens that the UE reports cell 1 in
Node B3 has greater strength than serving cell 1 in Node B1. This triggers an event 1D “Best Cell
Change” to cell 1 in Node B3, which supports only R99. The RNC must decide whether to switch to cell 1
in Node B3, which supports only R99, and initiate a Radio Bearer Reconfiguration.
Going from R6 to R99 is rare (only at the borders). So, the RNC determines that the UE is clearly going
away from the HSUPA coverage area and triggers a Radio Bearer Reconfiguration and hand down to R99.
R6-to-R99 Handovers (Initial)
7-12
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
R6R6--toto--R99 HandoversR99 Handovers (Initial(Initial))
UE
Serving Cell 1
E-DPDCH / E-DPCCH
E-AGCH/E-RGCH
E-RGCH
DPCCH/ DPDCH
E-HICH
E-HICH
E-DPDCH / E-DPCCH
DPCH
Triggers event 1D
DPCH
DPDCH/DPCCHDPCH
DPDCH /-DPCCH
Scheduling/Noise control
High-Speed Data/control
ACK/NACK
Voice, Sig / Pilot, TPC,TFCI
Voice, Sig / TPC, Pilot, TFCI
Voice, Sig / TPC,Pilot, TFCI
Voice, Sig / Pilot, TPC,TFCI
Voice, Sig / Pilot, T
PC, TFCI
Node B32
13
Active set cells cell 1
No E-DCHR99 Voice call
Node B22
1
3
Active set cells cell 1
E-DCH active set cell 1
Non serving RLSR99 Voice call
Active set cells cell 1
E-DCH active set cell 1
Serving cell 1R99 Voice call
Node B12
13
7-13
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
This example summarizes the R6-to-R99 handover preparation messages.
As shown in the figure, the UE is in cell 1, which is the HSUPA serving cell within NodeB1.
1. The UE transmits a Measurement Report message containing intra-frequency measurement
results, here assumed to be triggered by the event 1D “Change of Best Cell."
2. The SRNC performs the best cell change decision to cell 1, Node B3, which supports only R99.
3. The SRNC sends a synchronized Radio Link Reconfiguration Prepare message to the source Node
B1. Parameters that are sent mainly are E-DCH MAC-d flows to delete.
4. The source Node B1 responds with the Radio Link reconfiguration Ready.
5. The SRNC sends a Radio Link Reconfiguration Prepare message to the target Node B3, asking it
to perform synchronized Radio Link Reconfiguration. Parameters include RAB reconfiguration
information, UL and DL transport channels to be configured, RLC parameters to be modified,
DCH information like DPDCH /DPCCH codes, scrambling codes on UL and the DL scrambling
code.
6. The target Node B3 informs the SRNC that it is ready for RL reconfiguration by sending a Radio
Link Reconfiguration Ready message to the SRNC. Parameters include the DCH information
response.
7. The SRNC initiates a setup of new Iub data transport bearers using the ALCAP protocol. This
request contains the AAL2 binding identity to bind the Iub data transport bearer to the DCH.
R6-to-R99 Handovers (Prepare)
7-14
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
R6R6--toto--R99 HandoversR99 Handovers (Prepare)(Prepare)NodeB1
1
SRNC23
HSUPA Serving cell is (1,Node B1)1. Measurement Report (event 1D)
Node B31
7. Iub Bearer - DCH
3. RL Reconfiguration Prepare
4. RL Reconfiguration Ready
5. RL Reconfig Prepare
6. RL Reconfig Ready
2. Decision for best cell change to cell 1, Node B3 (only R99 support)
7-15
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
8. The SRNC transmits the NBAP Radio Link Reconfiguration Commit message to the source Node
B1. Carried parameters include activation time in the form of CFN. At the indicated activation
time, the source E-DCH Node B1 stops and the target DCH Node B3 starts transmitting on the
DCH to the UE.
9. The SRNC now transmits a Radio Link Reconfiguration Commit to the target Node B3, including
the activation time. Parameters include selected activation time in the form of a CFN.
10 The SRNC now sends a Radio Bearer Reconfiguration to the UE. Parameters include activation
time, DCH information, transport channel information, RLC parameters, logical channel
identifiers with priorities, and a new U-RNTI, if required.
11. On successful radio bearer reconfiguration, the UE sends a Radio bearer Reconfiguration
Complete message to the SRNC. Now, the target cell starts DCH transmission and the source cell
stops HS-DSCH transmission.
12. Now, the SRNC initiates release of the old Iub data E-DCH transport bearer using the ALCAP
protocol.
R6-to-R99 Handovers (Prepare)
7-16
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
R6R6--toto--R99 HandoversR99 Handovers (Prepare)(Prepare)NodeB1
1SRNC
.
23
9. RL Reconfig Commit
NodeB31
10. Radio Bearer Reconfiguration
11. Radio Bearer Reconfiguration Complete
12. E-DCH Bearer Release
8. RL Reconfiguration Commit
7-17
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
After Reconfiguration, UE still continues to be on soft handover between cell 1 of Node B1, cell 2 of
NodeB2 and cell 3 of Node B3 for voice and R99 uplink data service.
Both UL and DL carries signaling, power control commands, pilot bits and TFCI. The new DCH transport
channel is set up in all three Node Bs and signaled to the UE. During reconfiguration, the serving E-DCH
radio link is deleted and the corresponding UL and DL channels for HSUPA are removed.
R6-to-R99 Handovers (Final)
7-18
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
R6R6--toto--R99 HandoversR99 Handovers (Final)(Final)
UE
DPDCH/DPCCH
DPCH
DPCCH/ DPDCH
DPCH
DPDCH/DPCCH
DPCH
Reconfigured to R99 data
call
HSUPA link deleted
After reconfiguration, the UE is in soft handover with cell 1 of Node 1, cell 1 of Node B2 and cell 1 of Node B3 having
voice and UL data transfer
Voice, Data, Signaling/TPC, Pilot, TFCI
Voice, Signaling/TPC, Pilot, TFCI
C2
Node B32
1
Node B22
1
3
3
Node B12
1
Active Set Cells cell 1
R99 Voice call and R99 UL Data call 3
Active Set Cells cell 1
R99 voice call and R99 UL data call
Active Set Cells cell 1
R99 voice call and R99 UL data call
7-19
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
The initial deployment of UMTS R5 and R6 networks will not provide ubiquitous coverage. Since the
basis of UMTS’s Core Network (CN) architecture is the Global System for Mobile communications
(GSM) and the General Packet Radio System (GPRS), many GSM operators will be deploying UMTS as
their 3rd generation mobile wireless network. While existing GSM networks provide seamless coverage,
the 3G coverage area will be initially focused on the population centers.. Users will be provided with dual-
mode phones, which may operate in either UMTS or GSM mode. While in the city, users will be able to
take advantage of the advanced capabilities of the 3G UMTS network. However, upon driving out of the
UMTS coverage area, they must be handed to the GSM network if the service is to be kept active.
Note that some service or service capabilities might be unavailable or might need to be downgraded when
a handover from HSPA to GSM/GPRS or HSPA (HSDPA and HSUPA) to GPRS /EDGE occurs.
Cell reselection and handovers are possible between HSPA and GPRS/EDGE and vice versa. They are
also called Inter-RAT cell reselection and handovers. HSPA works only in RRC “Cell DCH” state.
So, there is no UE-initiated cell reselection directly from HSPA to GPRS. However, network-initiated cell
reselection, moving from HSPA to GPRS, is possible. The UTRAN sends an RRC Cell Change Order
message from the RNC to the UE to move the UE from an HSPA/R99 cell to the GPRS cell. Network-
assisted cell change can be ordered by the network if, for example, the network is loaded or for the
purposes of flow control.
The cell reselection and packet-switched handover procedures between HSPA and GPRS/EDGE and vice
versa are similar to R99.
R4 introduces the concept of GERAN, where the GSM/GPRS BSS can have an Iu interface with SGSN
and MSC/VLR. The old interfaces of A/GB mode can still exist and handovers between A/GB mode
GSM/GPRS networks and Iu mode GSM/GPRS are also supported. Similarly, handovers between the
UMTS Iu mode and GSM/GPRS Iu mode or UMTS Iu mode and GSM/GPRS A/GB are also possible.
Radio resource management strategies are now handled by the RRC when GSM/GPRS BSS operates in
the Iu mode.
HSPA – GPRS/EDGE Interworking
7-20
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
HSPA Cells GPRS CellsHSDSCH Serving CellE-DCH Serving Cell
Iu/GbIu
Iub A bis
Node B
RNC
Non-serving
RLS
Serving RLSNode B
GPRS Serving
Cell
SGSN Core
BTS BTS
BSC
HSPA – GPRS/EDGE Interworking
7-21
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
This slide illustrates UTRAN signaling procedures for UTRAN-to-GPRS cell reselection triggered by the
serving RNC. Please also refer to specs 25.931.
1. As soon as the trigger is detected by the SRNC, it initiates the handover to GSM/BSS by sending
the RRC Cell Change Order from UTRAN message to the UE.
2. The target GPRS cell is reselected by the UE and the radio connection to the GSM/BSS is now
established.
3. The GPRS Routing Area Update procedure is initiated by the UE by sending the GMM Routing
Area Update Request message to the SGSN.
4. The SGSN sends the RANAP SRNS Context Request message to the SRNC listing the PS RABs
for which context transfer shall be performed.
5. The RANAP SRNS Context Response message is sent by the SRNC in response to the SGSN,
which contains the context information of all referenced PS RABs whose transfer is successful.
6. To recover the buffered data, the SGSN transmits the RANAP SRNS Data Forward Command
message to the SRNC. The message includes the list of PS RABs whose data should be
forwarded, and necessary tunnelling information to be used for data forwarding.
Network-Initiated UMTS – GPRS Cell Reselection
7-22
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
NetworkNetwork--Initiated UMTS Initiated UMTS –– GPRS Cell GPRS Cell Reselection Reselection
UESRNC
Node B1
1. Cell Change order from UTRAN
2. Relocation to the target GPRS cell, radio link establishment in GSM/BSS
3. Routing Area Update Req.
4. SRNS CNXT Req.
5. SRNS CNXT Response
6. SRNS Data Forward Comm.
BSC
CNSGSN
7-23
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
7. For each PS RAB indicated by the SRNS Data Forward Command, the SRNC starts duplicating
and tunnelling the buffered data back to the SGSN.
8. To initiate release of the Iu connection with the UTRAN, the SGSN sends the RANAP Iu Release
Command message to the SRNC.
9. The SRNC sends the RANAP Iu Release Complete message to the SGSN when the data
forwarding timer (i.e.T DATAfwd ) of the RNC expires.
10. The release of Iu the data transport bearer using the ALCAP protocol is initiated by the SRNC.
Network-Initiated UMTS – GPRS Cell Reselection
7-24
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
NetworkNetwork--Initiated UMTS Initiated UMTS –– GPRS Cell GPRS Cell ReselectionReselection
UESRNCCN
SGSN Node B1
8. Iu Rel.Command
7. Forwarding of PDUs
9. Iu Rel.Complete
10. ALCAP Iu Bearer Rel.
BSC
7-25
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
11. The SGSN validates the UE’s presence in the new RA by sending the GMM Routing Area Update
Accept message to the UE. The message may contain a new P-TMSI that the network assigns to
the UE.
12. The GMM Routing Area Update Complete message is sent by the UE to acknowledge the
assignment of a new P-TMSI.
13. The SGSN and BSS can execute the BSS Packet Flow Context procedure and data transmission
can resume in the GPRS.
14. The NBAP Radio Link Deletion Request message is sent by the SRNC to the Node B to initiate
the release of the link.
15. The Node B confirms the release of the link by sending the NBAP Radio Link Deletion Response
message to the SRNC.
16. The Node B initiates the release of the Iub data transport bearer using the ALCAP protocol.
Network-Initiated UMTS – GPRS Cell Reselection
7-26
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
NetworkNetwork--Initiated UMTS Initiated UMTS –– GPRS GPRS Cell ReselectionCell Reselection
UE
SRNC Node B1
14. Radio Link Del. Req.
15. Radio LinkDel. Resp.
16. ALCAP Iu Bearer Rel.
11. Routing Area Update Acc.
12. Routing Area Update Comp.
13.Creating BSS flow CTX. data resume in GPRS
BSCCN
SGSN
7-27
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Handovers are used in cellular mobile systems to maintain connections as mobiles move between the
coverage areas of different base stations. The handover procedure involves four distinct algorithmic phases
that are discussed as mentioned in the figure.
Monitor: The first phase is monitoring, which includes communicating neighbor lists, taking signal
strength measurements of the current cell and cells in neighbor, and reporting the measurements.
In the monitoring phase, the mobile sends the current signal strength of the current cell and the cells in
the neighbor list to the network to facilitate the handover process. The network monitors the
transmission conditions between each MS and its current cell, and moves the MS to a new cell as
necessary.
Trigger: In the trigger or detection phase, the network detects that a handover may be required. This
can be based on a number of different factors such as signal strength, signal quality, interference,
distance, or traffic level in the current cell. The next phase of the handover process is the target cell
selection phase. In this phase, the network uses network topology information and measurements to
evaluate a list of candidate cells and select a target cell for the handover.
Target Selection: The target cell is selected in the target selection phase, and the channels for
transmission and reception are allocated to that cell. If no target cell is found, the mobile again returns
to the first phase that it is monitoring. It again starts monitoring the current as well as neighbor cells
until the target cell is selected.
Execution: In this phase, the MS changes to the new channel and resumes the call. Thus, the
handover is executed and completed successfully in this phase. If no acceptable target cell is available,
the handover can be attempted again later. After completion of this phase, it again enters the first
phase and starts monitoring the measurements of current cells and neighbor cells.
Handover Phases
7-28
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Handover PhasesHandover Phases
Monitor
Trigger
TargetSelection
Execution
NoTargetFound
• Communicating Neighbor List
• Taking Measurements
• Reporting Measurements
• Executing the Handover
• Completing the Handover
7-29
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
The UE performs different measurement procedures as controlled by the UTRAN in its idle mode and
connected mode.
When the UE is in idle mode, the system information elements are broadcast in System Information
Blocks (SIB). It receives measurement control information related to Inter–RAT measurement in system
information SIBs 11 and 12. These SIBs are transmitted from the RNC to the UE.
The UE measures its surrounding environment as instructed by the UTRAN. The UTRAN may control a
measurement in the UE either by using the broadcast system information and/or by sending a
Measurement Control message. In the broadcast system information, the measurement control information
is included in SIB 11 or 12.
When the UE is in connected mode, the RNC sends a Measurement Control message to the UE. The
Measurement Control message includes the following information:
• The type of measurement (for example, intra-frequency and/or inter-frequency measurement)
• The quantity the UE should measure (for example CPICH Ec/I0 – chip energy per total received
channel power density)
• The characteristics of the events that should trigger a measurement report, etc.
For example, an event can be that the signal strength of a monitored cell becomes stronger than the cell the
UE is currently connected to. Based on the requirement set by the UTRAN, the UE may need to send a
measurement report to inform the UTRAN for the consideration of a handover.
When an event ordered by the UTRAN occurs, the UE sends a Measurement Report message to the
UTRAN. This message includes the information related to the event as requested by the UTRAN’s
measurement control information. A measurement report is closely related to the initiation of a soft
handover. Thus, the UTRAN controls the entire measurement criteria.
Inter-RAT Measurements
7-30
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
If UE in idle mode
InterInter--RAT MeasurementsRAT Measurements
RNCNode B
CN PSTNIub IuUu
Measurement Control
UTRAN controls measurement criteria
If UE in connectedmode
BCH/PCCPCH
System Information Blocks(11/12)
RRC
Measurement Report
7-31
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
The Inter-RAT measurement parameters are sent to the UE in either System Information Blocks (SIB) 11
or 12, or in a Measurement Control message, depending on whether it is in idle state or connected state.
The key parameters included are shown in the figure.
Inter-RAT Cell Info List: This provides the UE with the list of GPRS neighbors. It includes the Base
Station Identification Code (BSIC) and the Absolute Radio Frequency Channel Number (ARFCN) for the
GPRS cells. Additionally, it also includes the compressed mode parameters.
Inter-RAT Measurement Quantity: This specifies the GPRS radio parameters that need to be measured
by the UE. For GPRS, it specifies whether the RSSI or path loss should be measured. It also involves
BSIC identification and verification.
Inter-RAT Measurement Criteria: This specifies the thresholds and hysteresis values to trigger
reporting of Inter-RAT measurements if threshold-based reporting is enabled. In addition, this message
(either SIB 11 or 12 or Measurement Control) includes parameters for periodic reporting if periodic
reporting is enabled.
Key Parameters for Inter-RAT
7-32
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Key Parameters for InterKey Parameters for Inter--RATRAT
Inter-RAT Measurement Criteria
Inter-RAT Measurement Quantity
Inter-RAT Cell Info List
Thresholds and Hysteresis values for triggering Inter-RAT measurement reports
GPRS Radio parameters to be measured• RSSI or Path loss• BSIC Identification and Verification
The list of GPRS Neighbors• BSIC for GPRS cells• BCCH ARFCN • Compressed mode parameters
7-33
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Since each neighboring cell in a UMTS system normally is operating on the same frequency as the serving
cell or set of cells (in the case of soft handover), the UMTS UE can perform intra-frequency measurements
while sending and receiving data on the physical layer RF interface. However, there are scenarios,
especially during early stages of UMTS deployment, in which ubiquitous coverage with a single UMTS
carrier is not the case. In these situations, the UTRAN can direct the UE to tune to a different UMTS
frequency or another radio access technology (RAT). This implies tuning to a different frequency to
measure the conditions and report to the UTRAN, thus initiating inter-frequency or inter-RAT hard
handovers.
The need for inter–frequency measurements requires some mechanism to allow the UE to continue with
the current operation and still measure the new frequency. The compressed mode procedure allows the
UE, with only one receiver, to obtain measurements and still continue with the original connection.
As compared to the HSDPA operation, the DPCH is given priority. This means, for example:
• If part of the HS-SCCH or HS-PDSCH overlaps with a downlink compression gap, the UE
neglects the HS-SCCH or HS-PDSCH transmission
• If part of a HS-DPCCH slot allocated for ACK/NACK or CQI overlaps with an uplink
transmission gap on the associated DPCH, the UE does not transmit the ACK/NACK or CQI
information in that slot
Inter-Frequency and Inter-RAT Measurements
7-34
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
InterInter--Frequency and Frequency and InterInter--RAT MeasurementsRAT Measurements
• How does the UE report on Inter-Frequency and Inter-RAT events?
• Compressed Mode – the UE and the UTRAN negotiate a mechanism to take time away from transmitting and receiving data to tune to a different frequency or radio access technology
• The DPCH-compressed mode has priority over HSDPA operation
7-35
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
As discussed earlier, the four phases of the UE, the trigger, and target selection phases are considered.
For the trigger and target selection phases, the manufacturer of the RNC designs both of these steps. The
following information provides clues regarding the structure of the algorithms:
• The handover algorithm must be designed so that the serving cell has an acceptable signal strength
and signal quality (RSCP, Ec/Io and Transport Channel, BLER in UMTS)
• The handover algorithm must take into account the signal strength of the neighbor cells, and a
handover can occur based a neighbor’s signal strength, not on the serving cells signal strength
• The service provider needs to set a priority of UMTS vs. GSM/GPRS
– This may trigger a handover to UMTS, not because of pool signal quality on the GSM cell,
but because the UMTS cell has a satisfactory quality and a higher preference.
Trigger and Target Selection
7-36
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Trigger and Target SelectionTrigger and Target Selection
• Decisions are proprietary in the RNC! • Decisions are based on cause for
handover:– Current cell signal strength and quality
• Signal strength - CPICH Ec/Io, RSCP• Quality - Transport channel BLER
– Adjacent cell signal strength• GSM/GPRS or UMTS cell
Monitor
Trigger
TargetSelection
Execution
NoTargetFound
7-37
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
This graph represents the Inter-Rat reporting event, and considers UMTS and GSM/GPRS measurement
quantities. The UMTS and GSM/GPRS threshold are as shown and time to trigger is mentioned. This
indicates the period of time during which the event condition has to be satisfied before sending a
measurement report.
Four measurement report events have been defined to support Inter-RAT measurements. The first event is
the most important, and is shown in the slide. The 3A event is defined so the mobile reports when the total
UMTS signal strength drops below a threshold and the best GSM/GPRS signal quality goes above a
threshold. These thresholds are independent. This can be key for the RNC to know when to initiate the
UMTS to GSM/GPRS handover.
Inter-RAT Reporting Event
7-38
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
InterInter--RAT Reporting EventRAT Reporting Event• Send measurement report only after the UMTS
quality drops below a threshold and the GSM quality is above a threshold
Time
Measurementquantity
Time to trigger
Reporting event 3A
UMTS
GSM
GSM Threshold
UMTS Threshold
7-39
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
The final phase of executing the handover is discussed in this slide. The HSPA-to-GPRS/EDGE handover
may occur in GERAN Gb mode as well as GERAN Iu mode. The key message that is used to trigger the
handover from HSPA to GPRS/EDGE is the Handover from UTRAN Command. The contents of an
HSPA Handover Command message are included as a parameter in the Handover from UTRAN
Command message. This Handover from UTRAN Command message includes all information needed by
the mobile to access the new GPRS/EDGE traffic channel that has been assigned. This message includes
the new ARFCN and TBFs (temporary block flow) assigned to the mobile. After the mobile has changed
frequencies and synchronized with the GPRS/EDGE system, the mobile sends a Handover Complete
message on the newly acquired traffic channel (PDTCH) if it is in Iu mode. For Gb mode, any RLC block
that is sent on the newly acquired traffic channel (PDTCH) and successfully decoded by the GPRS BSS is
considered a successful handover.
Executing the Handover
7-40
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Executing the HandoverExecuting the Handover
Monitor
Trigger
TargetSelection
Execution
NoTargetFound
GERAN GBMode
GERAN Iu Mode
• Handover from UTRAN command
• First RLC block that is decoded successfully
HSPA HO to GPRS/EDGE
• Handover from UTRAN command
• Handover complete
7-41
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
This slide illustrates an HSPA-to-GPRS/EDGE handover in Iu mode. Please refer to specs 25.922 for the
message flow and contents of each message on 25.413, 44.118 and 25.331.
1. The UE sends the Measurement Report whenever inter-RAT events are triggered to the RNC.
This includes the measurement results of the ARFCN, BSIC, and signal strength of the BCCH
ARFCN measured on neighboring GPRS cells.
2. Depending on the information in the Measurement Report, the serving RNC makes the decision to
relocate. The serving RNC sends a Relocation Required message to the SGSN. It contains
parameters like relocation type, cause, security algorithm, HS-DSCH MAC-d flow ID, E-DCH
MAC-d flow ID, security parameters and RAB identifier, source identifier and target Identifier.
3. The Core Network (CN) initiates the procedure by generating a Relocation Request message
toward the T-GSM-BSSS. The parameters are similar to Relocation Required parameters. A new
IU signaling Iu connection identifier is sent with the UE identity and RABs to be set up with RAB
identifiers.
4. After all necessary resources for accepted RABs including the initialized Iu user plane are
successfully allocated, the T-GSM-BSS sends a Relocation Request Acknowledge message to the
CN, which includes the RAB ID and Transport Layer Address, d-RNTI.
5. The Relocation Command message is sent by the CN (SGSN) to the serving RNC to indicate that
resources for the relocation are allocated in the T-GSM-BSS. If the target system (including target
CN) does not support all existing RABs, the Relocation Command message contains a list of
RABs, indicating all the RABs that are not supported by the target system. It also includes the
RAB ID and transport layer address.
6. The serving RNC sends a Handover from UTRAN Command message to the UE. The message is
used for handover from HSPA to GPRS/EDGE, as mentioned in our example. It includes UE
information elements such as integrity check information, activation time and RB information
elements such as the RAB information list to reconfigure.
HSPA-to-GPRS/EDGE Handover - Iu Mode
7-42
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
HSPAHSPA--toto--GPRS/EDGE Handover GPRS/EDGE Handover -- Iu Iu ModeMode
2. Relocation Required1. Measurement Report
5. Relocation Command6. Handover from UTRAN
Command
7. Relocation Detect
8. Handover Complete
9. Relocation Complete
10. Iu Release Command
11. Iu Release Complete
3. Relocation Request
4. Relocation Request ACK
T-BSSCN-SGSNS-BSCUE
7-43
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
7. The T-GSM-BSS sends a Relocation Detect message to the CN (SGSN) The Relocation Detect
message indicates the detection by the T-GSM-BSS of an SRNS relocation execution to the CN.
When the Relocation Detect message is sent, the T-GSM BSS starts serving -GSM-BSS
operation.
Upon receipt of the Relocation Detect message, the CN may switch the user plane from the
serving RNC to the T-GSM-BSS
8. When the UE has sent a Handover Complete message to the T-GSM-BSS, the UE initiates a
temporary block flow toward GPRS and sends a RA update request.
9. The T-GSM-BSS sends a Relocation Complete message to the CN (SGSN) to indicate that the T-
GSM-BSS has relocated the SRNS.
10. This message is sent by the CN to order the RNC to release all resources related to the Iu
connection. After the IU Release Command message has been sent, the CN does not send further
RANAP connection-oriented messages on this particular connection. The IU Release Command
message includes a Cause IE indicating the reason for the release (e.g., "Successful Relocation",
"Normal Release," "Release due to UTRAN Generated Reason," "Relocation Cancelled," and "No
Remaining RAB").
11.The SRNS sends an IU Release Complete message to the CN (SGSN) as a response to the IU
Release Command message. Reception of an IU Release Complete message terminates the
procedure in the CN. RRC connections are also released.
HSPA-to-GPRS/EDGE Handover - Iu Mode (continued)
7-44
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
HSPAHSPA--toto--GPRS/EDGE Handover GPRS/EDGE Handover -- Iu Iu Mode Mode (continued)(continued)
2. Relocation Required1. Measurement Report
5. Relocation Command6. Handover from UTRANCommand
7. Relocation Detect
8. Handover Complete
9. Relocation Complete
10. Iu Release Command
11. Iu Release Complete
3. Relocation Request
4. Relocation Request ACK.
T-BSSCN-SGSNS-BSCUE
7-45
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
The slide illustrates an HSPA-to-GPRS/EDGE handover in Gb mode. Please refer to specs 25.922 for the
message flow and contents of each message on 25.413, 48.018 and 25.331.
1. The UE sends the measurement report to the RNC, which includes the measurement results of
neighbor GPRS cells signal strength, BSIC and their BCCH ARFCN.
2. The serving RNC sends a Relocation Required message to the SGSN. The parameters are MS
radio Access capability, Inter RAT handover information, page mode, and Global TFI.
3. The SGSN initiates the PS Handover Request procedure by sending a PS-Handover-Request PDU
to the T-GSM-BSS, source BSS to target BSS information container. The container contains
mainly Inter-RAT handover information, Global TFI, etc.
4. After all necessary resources are successfully allocated, the T-GSM-BSS sends a PS Handover
Request Acknowledge message to the Core Network (CN), which consists of PS handover
command information from the NAS.
5. The Relocation Command message is sent by the CN (SGSN) to the serving RNC to indicate that
resources for the relocation are allocated in the T-GSM-BSS. This includes PS handover
command information.
6. The serving RNC sends a Handover from UTRAN Command message to the UE, which is used
for handover from HSPA to GPRS/EDGE as mentioned in our example. It includes a Gb mode
message, and the contents are from a PS handover command. The PS handover commands are TFI
assignment, Radio blocks and Timeslot, USF values and granularity for uplink transmission.
7. When the UE sends the first GPRS/EGPRS RLC block to the GSM BSS (and the BSS is able to
decode successfully), this indicates that the handover is successful.
8. The T-GSM-BSS initiates the PS Handover Complete procedure in the case of successful PS
handover on receipt of the first correct RLC data block from the MS in the target cell.
HSPA-to-GPRS/EDGE Handover - Gb Mode
7-46
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
HSPAHSPA--toto--GPRS/EDGE Handover GPRS/EDGE Handover -- Gb Gb ModeMode
2. Relocation Required1. Measurement Report
5. Relocation Command6. Handover from UTRANCommand
7. First RLC block on PDTCH successfully received then go to 8
8. PS Handover Complete
9. Iu Release Command
10. Iu Release Complete
3. PS handover Request
4. PS Handover Req ACK
T-BSSCN-SGSNSRNCUE
7-47
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
9. This message is sent by the CN (SGSN) to order the SRNC to release all resources related to the
Iu connection. After the IU Release Command message has been sent, the CN does not send
further RANAP connection-oriented messages on this particular connection. The IU Release
Command message includes a Cause IE indicating the reason for the release (e.g., "Successful
Relocation," "Normal Release," "Release due to UTRAN Generated Reason," "Relocation
Cancelled," and "No Remaining RAB").
10. The SRNS sends an IU Release Complete message to the CN (SGSN) in response to the IU
Release Command message. Receipt of an IU Release Command message terminates the
procedure in the CN. The RRC connections are also released.
HSPA-to-GPRS/EDGE Handover - Gb Mode (continued)
7-48
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
HSPAHSPA--toto--GPRS/EDGE Handover GPRS/EDGE Handover -- Gb Gb ModeMode (continued)(continued)
2. Relocation Required1. Measurement Report
5. Relocation Command6. Handover from UTRANCommand
7. First RLC block on PDTCH successfully received then go to 8
8. PS Handover Complete
9. Iu Release Command
10. Iu Release Complete
3. PS handover Request
4. PS Handover Req ACK
T-BSSCN-SGSNSRNCUE
7-49
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Both UMTS and the GPRS include reporting measurement procedures whose included parameters are
discussed individually.
While the mobile is active on a call, it sends a Packet Measurement Report or an Enhanced Measurement
Report in every SACCH block. This works out to a measurement report being sent periodically or when
polled by the network. Unlike with UMTS, GPRS sends a measurement report periodically versus when a
preset trigger is met.
The type of report that the mobile sends is dictated in the Measurement Information message. The
measurement report includes the required GPRS parameters for the serving cell such as the ARFCN,
BSIC, and Rxlev. The UMTS report includes the UARFCN, Scrambling code, and Ec/No or RSCP. Also
included (as needed) is the signal strength of the top 6 UMTS cells based on the type of measurement that
was instructed by the Measurement Information message.
Reporting Measurements
7-50
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Reporting MeasurementsReporting Measurements
• Packet Measurement Report: Sent periodically or when polled by the network
• Reports include:– GPRS
• ARFCN• BSIC• RxLev
– UMTS• UARFCN• Scrambling Code• Ec/No or RSCP
Monitor
Trigger
TargetSelection
Execution
NoTargetFound
Monitor
Trigger
TargetSelection
Execution
7-51
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
The final phase of executing the handover is discussed in this slide. The GPRS/EDGE-to-HSPA handover
may occur in Gb mode as well as Iu mode. The key message that triggers the handover from GPRS/EDGE
to HSPA in GERAN Gb Mode is the PS Handover Command. This message is sent on the packet-
associated control channel (PACCH) by the network to the mobile station to command the mobile station
to leave the current cell and change to a new cell.
After the mobile has changed frequencies and synchronized with the HSPA system, the mobile sends a
Handover Complete message on the newly acquired traffic channel.
In GERAN Iu Mode, the message for initiating GPRS/EDGE-to-HSPA Handover is the Intersystem
Handover to UTRAN Command message which is sent by the network to the mobile to initiate the
handover-to-UTRAN procedure. The Intersystem Handover to UTRAN Command message contains the
RRC transaction identifier, activation time, integrity check information, and integrity protection mode
information.
The mobile, on synchronization with changed frequencies of the HSPA system, sends a Handover to
UTRAN Complete message on the newly acquired traffic channel.
Executing the Handover
7-52
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Executing the HandoverExecuting the Handover
Monitor
Trigger
TargetSelection
Execution
NoTargetFound
GERAN GBMode
GERAN Iu Mode
• PS handover command
• Handover to UTRAN complete
• Intersystem handover to UTRAN command
• Handover to UTRAN complete
GPRS/EDGE to HSPA HO
7-53
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
The slide summarizes GPRS/EDGE to HSDPA handover in Iu mode. Please refer to specs 25.922 for the
message flow and contents of each message on 25.413, 44.118 and 25.331.
1. The UE sends the Packet Measurement Report to the S-BSS, which includes the measurement
results like the 3G cell list and their reporting quantity.
2. Depending on the Measurement Report, the serving S-BSS decides to Relocate.
The purpose of the Relocation Preparation procedure is to prepare relocation of the SRNS, with or
without involving the UE. The S-BSS initiates the procedure by sending a Relocation Required
message to the CN (SGSN). In the case of a GPRS/EDGE-to-HSPA handover, in the Relocation
Required message the serving S-BSS indicates the following parameters: the source RNC to target
RNC transparent container, which contains Inter-RAT handover information with Inter-RAT
capabilities.
3. The CN initiates the procedure by generating a Relocation Request message to the T-RNC. This
also consists of the source RNC to target RNC transparent container.
4. After all necessary resources for accepted RABs (including the initialised Iu user plane) are
successfully allocated, the T-RNC sends a Relocation Request Acknowledge message to the CN
that includes RABs that are reconfigured, Uplink and Downlink DCH transport channel
parameters, radio link information, HS-DSCH information, E-DCH information, HS-DSCH
MAC-d flows and E-DCH MAC-d flows.
5. The Relocation Command message is sent by the CN (SGSN) to the S-BSS to indicate that
resources assigned by the T-RNC. The CN forwards the same parameters sent by the TRNC to the
source BSS.
GPRS/EDGE-to-HSPA - Iu Mode
7-54
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
GPRS/EDGEGPRS/EDGE--toto--HSPA HSPA -- Iu ModeIu Mode
2. Relocation Required
1. PacketMeasurement Report
5. Relocation Command6. Intersystem to UTRAN
Handover Command7. Relocation Detect
8. Handover to UTRAN Complete
9. Relocation Complete
11. Iu Release Command
12. Iu Release Complete
3. Relocation Request
4. Relocation Request ACK
T-RNCCN-SGSNS-BSCUE
7-55
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
6. The Intersystem Handover to UTRAN Command message is sent by the S-BSS to the mobile to
initiate the handover to UTRAN procedure. The Intersystem Handover to UTRAN Command
message contains the RRC transaction identifier, activation time, integrity check information, and
Radio Bearer Reconfiguration message parameters. It consists of HS-DSCH MAC-d flows to add,
E-DCH MAC-d flows to add, logical channel identifiers, E-DCH information, HS-DSCH
information, and information on each radio Link.
7. The T-RNC sends a Relocation Detect message to the CN (SGSN) to indicate the detection by the
T-RNC of an S-BSS relocation execution. When the Relocation Detect message is sent, the T-
RNC starts serving –RNC operation.
Upon reception of the Relocation Detect message, the CN may switch the user plane from the S-
BSS to the T-RNC.
8. When the UE has sent the Handover to UTRAN Complete message to the T-RNC, it has changed
frequencies and is now synchronized with the HSPA system. The R99 channels on both DL and
UL for power control, Pilot, HSDPA UL and DL channels and UL and DL HSUPA channels are
now configured.
9. The T-RNC sends a Relocation Complete message to the CN (SGSN) to indicate the completion
by the T-RNC of the relocation of the S-BSS.
10. This message is sent by the CN to order the S-BSS to release all resources related to the Iu
connection. After the IU Release Command message has been sent, the CN does not send further
RANAP connection-oriented messages on this particular connection. The IU Release Command
message includes a Cause IE indicating the reason for the release (e.g., "Successful Relocation“).
11. The S-BSS sends an IU Release Complete message to the CN (SGSN) in response to the IU
Release Command message. Reception of the IU Release Complete message terminates the
procedure in the CN. The RRC connection with the GSM/BSS Iu mode is now released.
GPRS/EDGE-to-HSPA - Iu Mode (continued)
7-56
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
GPRS/EDGEGPRS/EDGE--toto--HSPA HSPA -- Iu ModeIu Mode(continued)(continued)
2. Relocation Required
1. PacketMeasurement Report
5. Relocation Command6. Intersystem to UTRAN
Handover Command7. Relocation Detect
8. Handover to UTRAN Complete
9. Relocation Complete
11. Iu Release Command
12. Iu Release Complete
3. Relocation Request
4. Relocation Request ACK
T-RNCCN-SGSNS-BSCUE
7-57
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
This slide summarizes GPRS/EDGE-to-HSPPA handover in Gb mode. Please refer specs 25.922 for the
message flow and contents of each message on 25.413, 48.018, 25.331 and 44.060.
1. The UE sends the Packet Measurement Report to the S-BSS, which includes the measurement
results. This includes the scrambling code of the cells, their Pilot Ec/No, and RSCP.
2. The S-BSS sends the PS Handover Required message to the CN (SGSN). This message consists
of the source RNC-to-Target RNC transparent container, which consists of the Inter-RAT
handover information with Inter-RAT capabilities.
3. The CN (SGSN) initiates the procedure by generating a Relocation Request message to the T-
RNC. The Core Network (CN) forwards the contents to the T-RNC that were previously sent by
the source BSS.
4. The target RNC sends a Relocation Request Acknowledge to the CN. The contents include a
target RNC to source RNC transparent container with handover to UTRAN command message
parameters.
5. After all necessary resources are successfully allocated, the CN (SGSN) sends a PS Handover
Request Acknowledge message to the S-BSS which contains the parameters of the above
message.
6. The S-BSS sends a PS Handover Command to the UE which includes the Handover to UTRAN
command parameters. The parameters carried include the RAB parameters to add list, E-DCH
MAC-d flow ID, HS-DSCH MAC-d flow ID, E-DCH information, HS-PDSCH information,
information for radio links, and the serving cell scrambling code.
7. The T-RNC sends the Relocation Detect message to the CN (SGSN). The purpose of the
Relocation Detect procedure is to indicate to the CN the detection by the T-RNC of an S-BSS
relocation execution. When the Relocation Detect message is sent, the T-RNC starts serving –
RNC operation.
GPRS/EDGE-to-HSPA - Gb Mode
7-58
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
GPRS/EDGEGPRS/EDGE--toto--HSPA HSPA -- Gb ModeGb Mode
2. Relocation Required
1. PacketMeasurement Report
5. Relocation Command6. Intersystem to UTRAN
Handover Command7. Relocation Detect
8. Handover to UTRAN Complete
9. Relocation Complete
11. Iu Release Command
12. Iu Release Complete
3. Relocation Request
4. Relocation Request ACK
T-RNCCN-SGSNS-BSCUE
7-59
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Upon reception of the Relocation Detect message, the CN may switch the user plane from the S-BSS to
the T-RNC.
8. When the UE has sent the Handover to UTRAN Complete message to the T-RNC, it has changed
frequencies and is now synchronized with the HSPA system. The mobile sends a Handover to
UTRAN Complete message on the newly acquired DPCCH logical channel.
9. The T-RNC sends a Relocation Complete message to the CN (SGSN) to indicate to the CN that
the T-RNC has relocated the S-BSS.
GPRS/EDGE-to-HSPA - Gb Mode (continued)
7-60
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
GPRS/EDGEGPRS/EDGE--toto--HSPA HSPA -- Gb ModeGb Mode(continued)(continued)
2. PS Handover Required
1. Packet Measurement Report
5. PS handover request Ack.
6. PS Handover Command
7. Relocation Detect
8. Handover to UTRAN complete
9. Relocation Complete
3. Relocation Request
4. Relocation Request Ack.
T-RNCSGSNS-BSCUE
7-61
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Summary
7-62
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
SummarySummary• There can be many reasons to hand over from R6/R5 to
R99. One of the reasons can be Best Cell Change, “event 1D”
• When Best Cell Change is initiated by the RNC, the target cell may only support R99, and, hence, the R6/R5 data call is reconfigured to an R99 call
• Handovers/Interworking between HSPA and GPRS/EDGE and vice versa is possible, and it is based on a UE Measurement Report triggered due to Inter-RAT measurement event results. The process is similar to R99–GPRS/EDGE interworking.
• HSPA-to-GPRS/EDGE and vice versa handover execution works in both Iu and Gb modes
• The messages and their corresponding parameters vary between Iu mode and Gb mode for HSPA–GPRS/EDGE handovers and vice versa
7-63
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
Review Questions
7-64
Mastering HSDPA/HSUPA Signaling
HSPA Interworking
Review QuestionsReview Questions
1. Is a UE-initiated cell reselection possible directly from HSPA to GPRS/EDGE?
2. What is the process initiated by the RNC for handing over an R5/R6 data call to R99?
3. To support the Iu mode of operation at GSM-BSS, what is the major change required at the BSS?
4. When can network-assisted cell reselection occur?
7-65
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-1
Appendix: HSDPA Call Setup Table of Contents Multi-Service Calls
1. RRC Connection Request (UL-CCCH)............................................ 3 2. RRC Connection Setup (DL-CCCH)................................................ 3 3. RRC Connection Setup Complete (UL-DCCH)................................. 5 4. Service Request.......................................................................... 7 5. Initial Direct Transfer (UL-DCCH)................................................. 7 6. Measurement Control (DL-DCCH)................................................. 7 7. Security Mode Command (DL-DCCH)............................................ 8 8. Security Mode Complete (UL-DCCH)............................................. 9 9. Uplink Direct Transfer (UL-DCCH).................................................9 10. Activate PDP Context Request...................................................... 10 11. Radio Bearer Setup (DL-DCCH).................................................... 10 12. Radio Bearer Setup Complete (UL-DCCH)......................................13 13. Radio Bearer Reconfiguration (DL-DCCH)………………..............…….. 13 14. Radio Bearer Reconfiguration Complete (UL-DCCH)....................... 14 15. Downlink Direct Transfer (DL-DCCH)............................................ 14 16. Activate PDP Context Accept........................................................ 14 17. Radio Bearer Reconfiguration (DL-DCCH)...................................... 15 18. Radio Bearer Reconfiguration Complete (UL-DCCH)....................... 16
Adding Voice over Existing Data
19. CM Service Request..................................................................... 17 20. Initial Direct Transfer (UL-DCCH)................................................. 17 21. Security Mode Command (DL-DCCH)............................................ 18 22. Security Mode Complete (UL-DCCH)............................................. 18 23. Setup......................................................................................... 18
Appendix: HSDPA Call Setup
A-2 Mastering HSDPA/HSUPA Signaling
Call Attempt 24. Uplink Direct Transfer (UL-DCCH)................................................. 19 25. Downlink Direct Transfer (DL-DCCH)............................................ 19 26. Call Proceeding........................................................................... 19 27. Radio Bearer Setup (DL-DCCH).................................................... 20 28. Radio Bearer Setup Complete (UL-DCCH) .................................... 22 29. Downlink Direct Transfer (DL-DCCH)............................................ 22 30. Alerting...................................................................................... 22
Call Setup
31. Downlink Direct Transfer (DL-DCCH)............................................ 22 32. Progress..................................................................................... 23 33. Connect......................................................................................23
Call Established
34. Connect Acknowledge................................................................. 23 35. Uplink Direct Transfer (UL-DCCH).................................................23
Releasing Data Call and Maintaining Voice Call
36. Deactivate PDP Context Request.................................................. 23 37. Uplink Direct Transfer (UL-DCCH)................................................. 24 38. Radio Bearer Release Complete (UL-DCCH)................................... 24 39. Signaling Connection Release (DL-DCCH)...................................... 24 40. Disconnect..................................................................................24 41. Uplink Direct Transfer (UL-DCCH)................................................. 24 42. Downlink Direct Transfer (DL-DCCH)............................................ 25 43. Release...................................................................................... 25
Releasing Voice Call – Call End
44. Release Complete....................................................................... 25 45. Uplink Direct Transfer (UL-DCCH)................................................. 25 46. RRC Connection Release (DL-DCCH)............................................. 25 47. RRC Connection Release Complete (UL-DCCH).............................. 26
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-3
Scenario The present document captures the Multi service calls which includes 1.Adding voice over existing data 2.Releasing voice and maintaining data 3.Finally releasing data The above scenario outlines the following messages and parameters
a) RRC related message and parameters b) RB setup related messages and parameters c) PDP Context activation
Multi-Service Calls 1.RRC Connection Request (UL-CCCH) Parameters Rb_Id : 0 Initial UE-Identity : tmsi-and-LAI plmn-Identity : MCC , MNC Location area code (LAC) : 52904 (Hex 0xCEA8) Establishment Cause : originating High Priority Signalling Protocol ErrorIndicator : noError 2.RRC Connection Setup (DL-CCCH) Parameters Rb_Id : 0 Initial UE-Identity : tmsi-and-LAI plmn-Identity : MCC , MNC Location area code (LAC) : 52904 (Hex 0xCEA8) rrc-Transaction Identifier : 0 new-U-RNTI SRNC-Identity S-RNTI rrc-State Indicator : cell-DCH capability Update Requirement ue-Radio Capability FDD Update Requirement : True RLC-Info Choice UL-RLC-Mode : ul-UM-RLC-Mode dl-RLC-Mode DL-RLC-Mode : dl-UM-RLC-Mode RB-MappingInfo : UL-Logical Channel Mappings : one Logical Channel UL-Transport Channel Type : dch mac-Logical Channel Priority : 2 DL-Logical Channel Mapping List : DL-Transport Channel Type : dch dch : 31
Appendix: HSDPA Call Setup
A-4 Mastering HSDPA/HSUPA Signaling
Logical Channel Identity : 1 polling Info timer Poll : tp140 poll-SDU : sdu1 last Transmission PDU-Poll : True poll Window : pw50 ul-Common Trans ChInfo mode Specific Info : fdd UL-TFCS TFCS : normal TFCI-Signaling Normal TFCI-Signaling Explicit TFCS-Configuration : complete complete Power Offset Information gain Factor Information Gain Factor Information : computed Gain Factors Computed Gain Factors : Gain Factor Information : signaled Gain Factors Signaled Gain Factors Mode Specific Info : fdd Gain Factor BetaC : 11 Gain Factor BetaD : 15 Reference TFC-ID : 0 UL-Add Reconf Trans Ch Info List : ul-Transport Channel Type : dch transport Channel Identity : 31 transport Format Set Transport Format Set : dedicated Trans Ch TFS Dedicated DynamicTF-Info List : rlc-Size : octetModeType1 OctetModeRLC-SizeInfoType1 : sizeType1 sizeType1 : 16 number Of Tb Size List : Number Of Transport Blocks : zero Logical Channel List : all Sizes semistaticTF-Information Channel Coding Type : convolutional convolutional : third rate Matching Attribute : 185 crc-Size : crc16 DL-Common Trans Ch Info mode Specific Info : fdd dl-Parameters : same As UL dl-Add Reconf Trans Ch Info List DL-Add Reconf Trans Ch Info List : dl-Transport Channel Type : dch
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-5
dl-transport Channel Identity : 31 power Control Algorithm Power Control Algorithm : algorithm1 algorithm1 : 1 dB (Raw value: 0) scrambling Code Type : long SC scrambling Code : 14350723 spreading Factor : sf64 puncturing Limit : pl1 dl-Common Information dl-DPCH-Info Common cfn Handling : initialise dl-DPCH-Power Control Info mode Specific Info : fdd dpc-Mode : singleTPC power Offset Pilot-pdpdch : 12 spreading Factor And Pilot SF512-AndPilot : sfd128 sfd128 : pb4 position Fixed Or Flexible : fixed mode Specific Info : fdd default DPCH-Offset Value : 177664 Primary CPICH-Info Primary Scrambling Code : 253 dl-DPCH-Info Per RL DL-DPCH-InfoPerRL : fdd PCPICH-Usage For Channel Est : may Be Used dpch-Frame Offset : 24064 DL-Channelisation Code List tpc-Combination Index : 0 3.RRC Connection Setup Complete (UL-DCCH) Parameters Rb_Id : 2 rrc-Transaction Identifier : 0 CN-Domain Identity : cs-domain start-Value cn-Domain Identity : ps-domain start-Value UE-Radio AccessCapability pdcp-Capability lossless SRNS-Relocation Support : False supportForRfc2507 : not Supported rlc-Capability total RLC-AM-Buffer Size : kb150 maximum RLC-Window Size : mws2047 maximum AM-Entity Number : am16 Transport Channel Capability
Appendix: HSDPA Call Setup
A-6 Mastering HSDPA/HSUPA Signaling
dl-Trans Ch Capability max No Bits Received : b6400 max Conv Code Bits Received : b6400 turbo Decoding Support Turbo Support : supported supported : b6400 max Simultaneous Trans Chs : e8 max Simultaneous CCTrCH-Count : 1 max Received Transport Blocks : tb32 max NumberOf TFC : tfc128 max Number Of TF : tf64 ul-Tran sCh Capability max No Bits Transmitted : b6400 max Conv Code Bits Transmitted : b6400 turbo Encoding Support Turbo Support : supported supported : b6400 max Simultaneous Trans Chs : e8 mode Specific Info : fdd max Transmitted Blocks : tb32 max Number Of TFC : tfc64 max Number Of TF : tf64 Rf-Capability physical Channel Capability downlink Phys Ch Capability max No DPCH-PDSCH-Codes : 1 max No Phys Ch Bits Received : b9600 supportForSF-512 : False support Of PDSCH : False simultaneous SCCPCH-DPCH-Reception Simultaneous SCCPCH-DPCH-Reception : not Supported Uplink Phys Ch Capability max No DPDCH-Bits Transmitted : b9600 support Of PCPCH : False UE-Multi Mode RAT-Capability multi RAT-Capability List multi mode Capability : fdd security Capability cipheringAlgorithmCap-spare15 : 0 cipheringAlgorithmCap-uea1 : 1 integrityProtectionAlgorithmCap-uia1 : 1 integrityProtectionAlgorithmCap-spare0 : 0 support For UE-GPS-Timing Of Cell Frames : False support For IPDL : False UE-Radio Access Capability Band FDD List : Radio Frequency Band FDD : fdd1900
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-7
ue-Powe Class : class3 tx Rx Frequency Separation : mhz190 measurement Capability Compressed Mode Measurement Capability FDD List : Radio Frequency Band FDD : fdd1900 dl-Measurements FDD : True ul-Measurements FDD : True radio Frequency Band FDD : spare3 UE-Power Class : class3 tx Rx Frequency Separation : mhz190 Measurement Capability rlc-Capability-r5-ext physical Channel Capability fdd-hspdsch : supported hsdsch-physical-layer-category : 12 4.Service Request Parameters Service Type Service Type : (0) Signalling Ciphering key sequence number Key sequence : (6) 6 P-TMSI Odd/even indication : (0) Even number of digits Type of identity : (4) TMSI/P-TMSI TMSI/P-TMSI : Hex 0xE0012C5E PDP context status NSAPI(7) : (0) SM state of the corresponding PDP context is PDP-INACTIVE. 5.Initial Direct Transfer (UL-DCCH) Parameters Rb_Id : 3 CN-Domain Identity : ps-domain intra Domain Nas Node Selector version : release99 CN-Type : gsm-Map-IDNNS gsm-Map-IDNNS routing basis : local PTMSI routing parameter initial DirectTransfer-v3a0ext 6.Measurement Control (DL-DCCH) Parameters
Appendix: HSDPA Call Setup
A-8 Mastering HSDPA/HSUPA Signaling
Rb_Id : 2 Measurement Control : r3 MeasurementControl-r3 rrc-Transaction Identifier : 0 measurement Identity : 1 Measurement Command : setup setup Measurement Type : intra Frequency Measurement Intra Freq Cell Info List Removed Intra Freq Cell List : remove All Intra Freq Cells New Intra Freq Cell List Intra Freq Cell ID : 0 Cell Info Cell Individual Offset : 0 Mode Specific Info : fdd Primary CPICH-Info Primary Scrambling Code : 253 Read SFN-Indicator : True tx-Diversity Indicator : False intra Freq Meas Quantity filter Coefficient : fc2 mode Specific Info : fdd intra Freq Meas Quantity-FDD : cpich-Ec-N0 Intra Freq Reporting Quantity active Set Reporting Quantities cpich-Ec-N0-reporting Indicator : True cpich-RSCP-reporting Indicator : True pathloss-reporting Indicator : False monitored Set ReportingQuantities ReportCriteria IntraFreqReportCriteria : intraFreqReportingCriteria intraFreqReportingCriteria eventCriteriaList IntraFreqEventCriteriaList : Intra Freq Event : e1a Intra Freq Event : e1b Intra Freq Event : e1c Intra Freq Event : e1d Measurement Report Transfer Mode : acknowledged Mode RLC Periodical Or Event Trigger : event Trigger 7.Security Mode Command (DL-DCCH) Parameters Rb_Id : 2 Integrity Check Info
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-9
Message Authentication Code rrc-Message Sequence Number : 1 Security Mode Command : r3 rrc-Transaction Identifier : 0 Security Capability cipheringAlgorithmCap-spare15 : 0 cipheringAlgorithmCap-uea1 : 1 cipheringAlgorithmCap-uea0 : 1 integrityProtectionAlgorithmCap-spare15 : 0 integrityProtectionAlgorithmCap-uia1 : 1 integrityProtectionAlgorithmCap-spare0 : 0 Ciphering Mode Info Ciphering Mode Command : start Restart Start Restart : UEa1 RB-Activation Time Info List : RB-Identity : 1 RLC-Sequence Number : 0 Integrity Protection Mode Command : start Integrity Protection Integrity Prot Init Number Integrity Protection Algorithm : uia1 CN-Domain Identity : PS-domain 8.Security Mode Complete (UL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 1 RRC-Transaction Identifier : 0 UL-Integ Protection Activation Info rrc-Message Sequence Number List rb-UL-Ciph Activation Time Info RB-Activation Time Info List : rb-Identity : 1 rlc-Sequence Number : 0 9.Uplink Direct Transfer (UL-DCCH) Parameters Rb_Id : 3 Integrity Check Info Message Authentication Code rrc-Message Sequence Number : 1 CN-Domain Identity : ps-domain nas-Message
Appendix: HSDPA Call Setup
A-10 Mastering HSDPA/HSUPA Signaling
10.Activate PDP Context Request Parameters Requested QoS Delay class : (0) Subscribed delay class Reliability class : (0) Subscribed reliability class Peak throughput : (0) Subscribed peak throughput Precedence class : (0) Subscribed precedence Mean throughput : (0) Subscribed mean throughput Traffic Class : (0) Subscribed traffic class Delivery order : (0) Subscribed delivery order Delivery of erroneous SDU : (0) Subscribed delivery of erroneous SDUs Maximum SDU size : (0) Subscribed maximum SDU size Maximum bit rate for uplink : (0) Subscribed Maximum bit rate for downlink : (0) Subscribed Residual BER : (0) Subscribed residual BER SDU error ratio : (0) Subscribed SDU error ratio Transfer delay : (0) Subscribed transfer delay Traffic Handling priority : (0) Subscribed traffic handling priority Guaranteed bit rate for uplink : (0) Subscribed Guaranteed bit rate for downlink : (0) Subscribed Requested PDP address PDP type organisation : (1) IETF allocated address PDP type number : (33) IPv4 address No PDP address included Access point name Access Point Name : isp.cingular Protocol configuration options Configuration protocol : (0) PPP Protocol ID : Protocol ID : CHAP (Hex 0xC223) 11.Radio Bearer Setup (DL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code rrc-Message Sequence Number : 2 Radio Bearer Setup-r5 activation Time : 52 new-H-RNTI RRC-State Indicator : cell-DCH CN-Domain Identity : ps-domain re-Establishment Timer : useT315 rb-Information Setup List RB-Information Setup List-r5 : rb-Identity : 16
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-11
pdcp-Info lossless SRNS-Reloc Support Lossless SRNS-Reloc Support : not Supported pdcp-PDU-Header : absent RLC-InfoChoice-r5 : rlc-Info-r5 UL-RLC-Mode : ul-AM-RLC-Mode ul-AM-RLC-Mode transmission Window Size : tw128 timer RST : tr250 max-RST : rst4 Polling Info timer Poll : tp160 last Transmission PDU-Poll : True last Retransmission PDU-Poll : True poll Window : pw50 DL-RLC-Mode-r5 : dl-AM-RLC-Mode-r5 dl-AM-RLC-Mode-r5 dl-RLC-PDU-size OctetModeRLC-SizeInfoType1 : sizeType2 in Sequence Delivery : True receiving Window Size : rw2047 dl-RLC-Status Info timer Status Prohibit : tsp70 missing PDU-Indicator : True rlc-One Sided ReEst : False RB-MappingInfo-r5 : UL-Logical Channel Mappings : one Logical Channel One Logical Channel ul-Transport Channel Type UL-Transport Channel Type : dch dch : 24 rlc-Size List : configured mac-Logical Channel Priority : 8 DL-LogicalChannelMappingList-r5 : DL-TransportChannelType-r5 : hsdsch hsdsch : 1 RB-Identity : 1 UL-Common Transort Channel Info mode Specific Info : fdd ul-TFCS TFCS : normal TFCI-Signaling Normal TFCI-Signaling Explicit TFCS-Configuration : complete complete Power Offset Information gain Factor Information
Appendix: HSDPA Call Setup
A-12 Mastering HSDPA/HSUPA Signaling
Gain Factor Information : computed Gain Factors ul-Add Reconfiguration Transport Channel Info List UL-Add Reconfiguration Transport Channel Info List : ULl-Transport Channel Type : dch transport Channel Identity : 31 Transport Format Set : dedicated Trans Ch TFS Dedicated Trans Ch TFS Dedicated Dynamic TF-Info List : rlc-Size : octetModeType1 Number Of Transport Blocks : one Channel Coding Type : convolutional convolutional : third rate Matching Attribute : 230 crc-Size : crc16 dl-Parameters : dl-DCH-TFCS TFCS : normal TFCI- Signaling DL-Add Reconf Trans Ch Info List-r5 : dl-Transport Channel Type DL-TrCH-Type Id1-r5 : hsdsch tfs-Signalling Mode : hsdsch Harq Info number Of Processes : 6 memory Partitioning : implicit add Or Reconf MAC-d Flow MAC-hs-Add Reconfiguration Queue-List : mac-hs Queue Id : 1 mac-d FlowId : 1 reordering Release Timer : rt50 mac-hs Window Size : mws16 MAC-d-PDU-Size Info-List : mac-d-PDU-Size : 336 mac-d-PDU-Index : 1 UL-Channel Requirement-r5 : ul-DPCH-Info UL-DPCH-Power Control Info-r5 : fdd DPCCH-Power Offset : -98 Power Control Algorithm : algorithm1 delta ACK : 5 delta NACK : 5 ack-NACK-repetition-factor : 1 scrambling Code Type : long SC scrambling Code : 14350723 spreading Factor : sf16 puncturing Limit : pl0-96 mode Specific Phys Ch Info : fdd DL-HSPDSCH-Information HS-SCCH-Info
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-13
mode Specific Info : fdd HS-SCCH Channelisation Code Info Measurement-feedback-Info mode Specific Info : fdd measurement Power Offset : 16 feedback-cycle : fc8 cqi-Repetition Factor : 1 delta CQI : 4 dl-Common Information dl-DPCH-Info Common cfn Handling : maintain power Offset Pilot-pdpdch : 12 spreading Factor And Pilot position Fixed Or Flexible : fixed tfci-Existence : False mode Specific Info : fdd mac-hs Reset Indicator: true Primary CPICH-Info Primary Scrambling Code : 253 Serving HSDSCH-RL-indicator : True dl-DPCH-InfoPerRL DL-DPCH-InfoPerRL-r5 : fdd pCPICH-Usage For Channel Est : may Be Used dpch-Frame Offset : 24064 DL-Channelisation Code List : sf-And Code Number tpc-Combination Index : 0 12.Radio Bearer Setup Complete (UL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code rrc-Message Sequence Number : 2 rrc-Transaction Identifier : 0 13.Radio Bearer Reconfiguration (DL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code rrc-Message Sequence Number : 3 Radio Bearer Reconfiguration : later-than-r3 rrc-Transaction Identifier : 0 Radio Bearer Reconfiguration-r5 RRC-State Indicator : cell-DCH
Appendix: HSDPA Call Setup
A-14 Mastering HSDPA/HSUPA Signaling
RB-Information Reconfiguration List-r5 : rb-Identity : 2 UL-RLC-Mode : ul-AM-RLC-Mode transmission Window Size : tw32 timer RST : tr550 max-RST : rst1 Polling Info timer Poll : tp310 poll-SDU : sdu1 last Transmission PDU-Poll : True last Retransmission PDU-Poll : True poll Window : pw50 DL-RLC-Mode-r5 : dl-AM-RLC-Mode-r5 dl-AM-RLC-Mode-r5 dl-RLC-PDU-size sizeType1 : 16 in Sequence Delivery : True receiving Window Size : rw32 dl-RLC-Status Info timer Status Prohibit : tsp230 missing PDU-Indicator : True DL-HSPDSCH-Information 14.Radio Bearer Reconfiguration Complete (UL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code rrc-Message Sequence Number : 3 rrc-Transaction Identifier : 0 15.Downlink Direct Transfer (DL-DCCH) Parameters Rb_Id : 3 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 1 RRC-Transaction Identifier : 0 CN-Domain Identity : ps-domain nas-Message 16.Activate PDP Context Accept Parameters TI flag : (1) The message is sent to the side that originates the TI Transaction identifier : 0 Protocol discriminator : (10) GPRS session management messages
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-15
Negotiated QoS Delay class : (1) Delay class 1 Reliability class : (3) Unacknowledged GTP and LLC; Acknowledged RLC, Protected Peak throughput : (9) Up to 256 000 octets/s Precedence class : (2) Normal priority Mean throughput : (31) Best effort Traffic Class : (3) Interactive class Delivery order : (2) Without delivery order ('no') Delivery of erroneous SDU : (3) Erroneous SDUs are not delivered ('no') Maximum SDU size : (150) 1500 octets Maximum bit rate for uplink : (151) 2048 kbps Maximum bit rate for downlink : (151) 2048 kbps Residual BER : (7) 1*10E-5 SDU error ratio : (4) 1*10E-4 Transfer delay : (32) 1000 ms Traffic Handling priority : (1) Priority level 1 Guaranteed bit rate for uplink : (16) 16 kbps Guaranteed bit rate for downlink : (64) 64 kbps Radio priority level value : (1) Priority level 1 (highest) Packet data protocol address PDP type organization : (1) IETF allocated address PDP type number : (33) IPv4 address Address : 166.214.152.248 Protocol configuration options 17.Radio Bearer Reconfiguration (DL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 5 RRC-Transaction Identifier : 0 Radio BearerReconfiguration-r5 activation Time : 120 rrc-State Indicator : cell-DCH specification Mode : complete RB-Information Reconfig List-r5 : UL-RLC-Mode : ul-AM-RLC-Mode transmission Window Size : tw512 timer RST : tr250 max-RST : rst4 polling Info timer Poll : tp110
Appendix: HSDPA Call Setup
A-16 Mastering HSDPA/HSUPA Signaling
last Transmission PDU-Poll : True poll Window : pw50 dl-RLC-Mode-r5 DL-RLC-Mode-r5 : dl-AM-RLC-Mode-r5 dl-AM-RLC-Mode-r5 dl-RLC-PDU-size Octet Mode RLC-Size InfoType1 : sizeType2 part1 : 2 in Sequence Delivery : True receiving Window Size : rw2047 DL-RLC-Status Info timer Status Prohibit : tsp100 missing PDU-Indicator : True RLC-One Sided ReEst : False UL-Common Transport Channel Info mode Specific Info : fdd TFCS : normal TFCI-Signaling Explicit TFCS-Configuration : complete Gain Factor Information : computed Gain Factors UL-Add Reconfiguration Transport Channel Info List Dedicated Dynamic TF-Info List : RLC-Size : octetModeType1 Number Of Tb Size List : crc-Size : crc16 ul-Transport Channel Type : dch transport Channel Identity : 24 Transport Format Set : dedicated Trans Ch TFS Dedicated Trans Ch TFS Dedicated Dynamic TF-Info List rlc-Size : octetModeType1 octetModeType1 Number Of Transport Blocks : zero Logical Channel List : all Sizes Semistatic TF-Information Channel Coding Type : turbo Rate Matching Attribute : 110 crc-Size : crc16 UL-Channel Requirement-r5 : ul-DPCH-Info mode Specific Info : fdd scrambling Code Type : long SC scrambling Code : 14350723 spreading Factor : sf4 puncturing Limit : pl0-72 mode Specific Phys Ch Info : fdd 18.Radio Bearer Reconfiguration Complete (UL-DCCH)
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-17
Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code rrc-Message Sequence Number : 4 rrc-Transaction Identifier : 0 1.Adding Voice over existing data 19.CM Service Request Parameters CM service type Service type : (1) Mobile originating call establishment or packet mode connection establishment Mobile station classmark Revision level : (2) Mobile station supporting R99 or later versions of the protocol ES IND : (1) "Controlled Early Classmark Sending" option is implemented in the MS A5/1 : (0) Encryption algorithm A5/1 available RF Power Capability : (3) class 4 PS capability (pseudo-synchronization capability) : (1) PS capability present SS Screening Indicator (defined in TS 24.080) : 1 SM capability (MT SMS pt to pt capability) : (1) Mobile station supports mobile terminated point to point SMS VBS notification reception : (0) No VBS capability or no notifications wanted VGCS notification reception : (0) No VGCS capability or no notifications wanted FC Frequency Capability : (0) (GSM900 only:) The MS does not support E-GSM or R-GSM CM3 : (1) The MS supports options that are indicated in classmark 3 IE LCS VA capability : (0) LCS value added location request notification capability not supported UCS2 : (0) The ME has a preference for the default alphabet (defined in GSM 03.38) over UCS2. SoLSA : (0) The ME does not support SoLSA. CMSP: CM Service Prompt : (0) "Network initiated MO CM connection request" not supported. A5/3 : (0) Encryption algorithm A5/3 not available A5/2 : (1) Encryption algorithm A5/2 available Mobile identity Odd/even indication : (0) Even number of digits Type of identity : (4) TMSI/P-TMSI TMSI/P-TMSI : Hex 0x0125A3D4 20.Initial Direct Transfer (UL-DCCH) Parameters Rb_Id : 3 Integrity Check Info Message Authentication Code rrc-Message Sequence Number : 2 CN-Domain Identity : cs-domain intra Domain Nas Node Selector version : release99 CN-Type : gsm-Map-IDNNS
Appendix: HSDPA Call Setup
A-18 Mastering HSDPA/HSUPA Signaling
gsm-Map-IDNNS Routing basis : local PTMSI Routing parameter nas-Message initial Direct Transfer-v3a0ext 21.Security Mode Command (DL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 11 RRC-Transaction Identifier : 0 Security Capability cipheringAlgorithmCap-spare15 : 0 cipheringAlgorithmCap-uea1 : 1 integrityProtectionAlgorithmCap-uia1 : 1 integrityProtectionAlgorithmCap-spare0 : 0 Ciphering Mode Info ciphering Mode Command Ciphering Mode Command : start Restart RB-DL-Ciph Activation Time Info RB-Activation Time Info List : rb-Identity : 1 rlc-Sequence Number : 0 Integrity Protection Mode Command : modify dl-Integrity Prot Activation Info Integrity Protection Algorithm : uia1 CN-Domain Identity : cs-domain 22.Security Mode Complete (UL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 10 RRC-Transaction Identifier : 0 UL-Integ Prot Activation Info RRC-Message Sequence Number List : rb-UL-Ciph Activation Time Info RB-Activation Time Info List : RB-Identity : 1 RLC-Sequence Number : 0 23.Setup Parameters
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-19
Bearer capability 1 Radio channel requirement : (3) The MS supports at least full rate speech version 1 and half rate speech version 1. The MS has a greater preference for full rate speech version 1. Coding standard : (0) GSM standardized coding as described below Transfer mode : (0) circuit mode Information transfer capability : (0) speech Coding : (0) octet used for extension of information transfer capability CTM : (0) CTM text telephony is not supported Speech version indication : (4) GSM full rate speech version 3 Coding : (0) octet used for extension of information transfer capability Speech version indication : (2) GSM full rate speech version 2 Called party BCD number Type of number : (0) Unknown Numbering plan identification : (1) ISDN/telephony numbering plan (Rec. E.164/E.163) Number : 9727575744 CC Capabilities Maximum number of supported bearers : 1 bearer supported PCP : (0) The mobile station does not support the Prolonged Clearing Procedure. DTMF : (1) The mobile station supports DTMF. Maximum number of speech bearers : 0 Call Attempt 24.Uplink Direct Transfer (UL-DCCH) Parameters Rb_Id : 3 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 3 CN-Domain Identity : cs-domain nas-Message 25.Downlink Direct Transfer (DL-DCCH) Parameters Rb_Id : 3 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 2 Downlink DirectTransfer-r3 RRC-Transaction Identifier : 1 CN-Domain Identity : cs-domain nas-Message 26.Call Proceeding Parameters Time: 12:25:04.21
Appendix: HSDPA Call Setup
A-20 Mastering HSDPA/HSUPA Signaling
Command Code : 16 Length : 19 Log Code (Hex) : 0x713A 1.25 ms/40 counter (32 kHz clock) : 57 CFN : 16 1.25 ms counter : 60613325 Direction : (0) From network Message length : 2 Transaction identifier : 8 Protocol discriminator : (3) Call control; call related SS messages 27.Radio Bearer Setup (DL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 12 RRC-Transaction Identifier : 0 Radio Bearer Setup-r5 activation Time : 132 rrc-State Indicator : cell-DCH RAB-InformationSetupList-r5 : RAB-Identity : gsm-MAP-RAB-Identity gsm-MAP-RAB-Identity : 00000001 cn-Domain Identity : cs-domain re-Establishment Timer : useT314 RLC-InfoChoice-r5 : rlc-Info-r5 UL-RLC-Mode : ul-TM-RLC-Mode ul-TM-RLC-Mode dl-RLC-Mode-r5 DL-RLC-Mode-r5 : dl-TM-RLC-Mode RB-MappingInfo-r5 : UL-Logical Channel Mappings : one Logical Channel UL-Transport Channel Type : dch dch : 8 rlc-Size List : configured mac-Logical Channel Priority : 7 DL-Logical Channel Mapping List-r5 : dl-Transport Channel Type DL-TransportChannelType-r5 : dch dch : 8 UL-Common Trans Ch Info mode Specific Info : fdd ul-TFCS TFCS : normal TFCI-Signalling Explicit TFCS-Configuration : complete
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-21
Power Offset Information gain Factor Information Gain Factor Information : computed Gain Factors Computed Gain Factors : 0 Number Of Tb Size List : Number Of Transport Blocks : zero Logical Channel List : allSizes Semistatic TF-Information Channel Coding Type : convolutional convolutional : third rate Matching Attribute : 185 crc-Size : crc16 DL-Add Reconfiguration Transport Channel Info List-r5 : dl-Transport Channel Type DL-TrCH-TypeId1-r5 : dch dch : 31 tfs-Signalling Mode : explicit-config explicit-config Transport Format Set : dedicated Trans Ch TFS rlc-Size : octetModeType1 number Of Tb Size List : dch-Quality Target bler-Quality Value : -2.0 UL-ChannelRequirement-r5 : ul-DPCH-Info ul-DPCH-Info mode Specific Info : fdd scrambling Code Type : long SC scrambling Code : 14350723 spreading Factor : sf16 tfci-Existence : True puncturing Limit : pl0-76 mode Specific Phys Ch Info : fdd DL-DPCH-Info Common cfn Handling : maintain mode Specific Info : fdd power Offset Pilot-pdpdch : 12 spreading Factor And Pilot SF512-And Pilot : sfd128 sfd128 : pb4 position Fixed Or Flexible : fixed tfci-Existence : False dl-Information Per RL-List DL-InformationPerRL-List-r5 : Mode Specific Info : fdd Primary CPICH-Info Primary Scrambling Code : 253
Appendix: HSDPA Call Setup
A-22 Mastering HSDPA/HSUPA Signaling
Serving HSDSCH-RL-indicator : True dl-DPCH-InfoPerRL DL-DPCH-InfoPerRL-r5 : fdd PCPICH-Usage For Channel Est : may Be Used dpch-Fram eOffset : 24064 DL-Canalization Code List : SF-And Code Number SF512-AndCodeNumber : sf128 sf128 : 9 tpc-Combination Index : 0 28.Radio Bearer Setup Complete (UL-DCCH) Parameters Rb_Id : 2 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 11 RRC-Transaction Identifier : 0 count-C-Activation Time : 120 29.Downlink Direct Transfer (DL-DCCH) Parameters Rb_Id : 3 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 3 Downlink Direct Transfer-r3 rrc-Transaction Identifier : 2 CN-Domain Identity : cs-domain nas-Message 30.Alerting Parameters Transaction identifier : 8 Protocol discriminator : (3) Call control; call related SS messages Message type : 1 Progress indicator Coding standard : (3) Standard defined for the GSM PLMNS Location : (4) Public network serving the remote user Progress description : (8) In-band information or appropriate pattern now available Call Setup 31.Downlink Direct Transfer (DL-DCCH) Parameters Rb_Id : 3 Integrity Check Info Message Authentication Code
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-23
RRC-Message Sequence Number : 4 Downlink Direct Transfer : r3 RRC-Transaction Identifier : 3 CN-Domain Identity : CS-domain nas-Message 32.Progress Transaction identifier : 8 Protocol discriminator : (3) Call control; call related SS messages Message type : 3 Progress indicator Coding standard : (3) Standard defined for the GSM PLMNS Location : (2) Public network serving the local user Progress description : (2) Destination address in non-PLMN/ISDN 33.Connect Parameters Transaction identifier : 8 Protocol discriminator : (3) Call control; call related SS messages Progress indicator Coding standard : (3) Standard defined for the GSM PLMNS Location : (2) Public network serving the local user Progress description : (32) Call is end-to-end PLMN/ISDN Call Established 34.Connect Acknowledge Parameters Transaction identifier : 0 Protocol discriminator : (3) Call control; call related SS messages Message type : 15 35.Uplink Direct Transfer (UL-DCCH) Parameters Rb_Id : 3 Integrity Check Info message Authentication Code RRC-Message Sequence Number : 4 CN-Domain Identity : cs-domain nas-Message 2.Releasing Data call and maintaining Voice call 36.Deactivate PDP Context Request Parameters TI flag : (0) The message is sent from the side that originates the TI
Appendix: HSDPA Call Setup
A-24 Mastering HSDPA/HSUPA Signaling
Transaction identifier : 0 Protocol discriminator : (10) GPRS session management messages Message type : 70 SM cause Cause value : (36) Regular deactivation78 Tear down indicator (TDI) flag : (1) Tear down requested 37.Uplink Direct Transfer (UL-DCCH) Parameters Rb_Id : 3 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 4 CN-Domain Identity : cs-domain nas-Message 38.Radio Bearer Release Complete (UL-DCCH) Rb_Id : 2 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 12 RRC-Transaction Identifier : 0 39.Signalling Connection Release (DL-DCCH) Parameters Rb_Id : 2 Message length : 6 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 15 Signalling Connection Release : r3 RRC-Transaction Identifier : 0 CN-Domain Identity : ps-domain 40.Disconnect Parameters Transaction identifier : 0 Protocol discriminator : (3) Call control; call related SS messages Message type : 37 Cause Coding standard : (3) Standard defined for the GSM PLMNS Location : (0) user cause value : (16) Normal call clearing 41.Uplink Direct Transfer (UL-DCCH) Parameters
Appendix: HSDPA Call Setup
Mastering HSDPA/HSUPA Signaling A-25
Rb_Id : 3 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 6 CN-Domain Identity : cs-domain nas-Message 42.Downlink Direct Transfer (DL-DCCH) Parameters Rb_Id : 3 Message length : 10 Integrity Check Info message Authentication Code RRC-Message Sequence Number : 8 Downlink Direct Transfer : r3 RRC-Transaction Identifier : 3 CN-Domain Identity : cs-domain nas-Message 43.Release Parameters Transaction identifier : 8 Protocol discriminator : (3) Call control; call related SS messages Message type : 45
3. Releasing Voice call Call End 44.Release Complete Parameters Transaction identifier : 0 Protocol discriminator : (3) Call control; call related SS messages Message type : 42 45.Uplink Direct Transfer (UL-DCCH) Parameters Rb_Id : 3 Message length : 10 Integrity Check Info message Authentication Code RRC-Message Sequence Number : 7 CN-Domain Identity : cs-domain nas-Message 46.RRC Connection Release (DL-DCCH) Parameters
Appendix: HSDPA Call Setup
A-26 Mastering HSDPA/HSUPA Signaling
Rb_Id : 1 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 1 RRC Connection Release : r3 RRC-Transaction Identifier : 0 n-308 : 1 release Cause : normal Event 47.RRC Connection Release Complete (UL-DCCH) Parameters Rb_Id : 1 Message length : 6 Integrity Check Info Message Authentication Code RRC-Message Sequence Number : 1 RRC-Transaction Identifier : 0
Acronyms
Mastering HSDPA/HSUPA Signaling B-1
Acronyms
Acronyms
B-2 Mastering HSDPA/HSUPA Signaling
Acronyms
Mastering HSDPA/HSUPA Signaling B-3
Acronyms 2.5G Wireless Systems in-between 2nd and 3rd generation 2G Second Generation Wireless Systems 3G Third Generation Wireless Systems 3GPP Third Generation Partnership Project 3GPP2 Third Generation Partnership Project 2 8-PSK 8 Phase Shift Keying 16QAM 16 Quadrature Amplitude Modulation A/D Analog to Digital AA Anonymous Access AAA Authentication, Authorization and Accounting AAL ATM Adaptation Layer AAL2 ATM Adaptation Layer type 2 AAL5 ATM Adaptation Layer type 5 AAS Adaptive Antenna System AC (AuC) Authentication Center ACELP Algebraic Code Excited Linear Prediction ACH Access Channel ACK Acknowledge or Acknowledgement ACN Access Channel Number ARFCN Absolute Radio Frequency Channel Number AGCH Access Grant Channel AGW Access Gateway AI Acquisition Indication AICH Acquisition Indication Channel A-Key Authentication Key ALCAP Access Link Control Application Part AM Acknowledged Mode AM Amplitude Modulation AMC Adaptive Modulation and Coding AMR Adaptive Multi-Rate AN Access Network AP Access Point API Application Program Interface APN Access Point Name ARQ Automatic Repeat request AS Access Stratum ATM Asynchronous Transfer Mode
Acronyms
B-4 Mastering HSDPA/HSUPA Signaling
AuC Authentication Center AUTN Authentication Token AWI Alert with Information BCCH Broadcast Control Channel BCFE Broadcast Control Functional Entity BCH Broadcast Channel BCMCS Broadcast and Multicast Services BER Bit Error Rate BGP Border Gateway Protocol BPSK Binary Phase Shift Keying BS Base Station BSC Base Station Controller BSIC Base Station Identity Code BSS Base Station System BSSMAP Base Station System Mobile Application Part BTS Base Station Transceiver System, Base Transceiver Station BW Bandwidth CAC Connection Admission Control CC Call Control CC Channel Coding CC Conference Call CCCH Common Control Channel CCH Control Channel CCITT Consultative Committee of the Int’l Telegraph and Telephone CCS Common Channel Signaling CCTrCH Coded Composite Transport Channel CD Call Delivery CDMA Code Division Multiple Access CELP Code Excited Linear Predictive CGF Charging Gateway Function CI Cell Identity CID Channel ID CID Circuit Identification CID Connection Identifier CK Ciphering Key CM Connection Management CN Core Network CP Cyclic Prefix CPCH Common Packet Channel CPI Capability Preference Information CPICH Common Pilot Channel CQI Channel Quality Indicators CQICH Channel Quality Indication Channel CQM Core Quality of Service Manager
Acronyms
Mastering HSDPA/HSUPA Signaling B-5
CQM Core Quality of Service Manager CRC Cyclic Redundancy Check CRNC Controlling Radio Network Controller C-RNTI Cell Radio Network Temporary Identity CS Circuit-Switched CSC Customer Service Center CS-CN Circuit Switched Core Network CSD Circuit-Switched Data CSMA/CA Carrier Sense Multiple Access/Collision Avoidance CSMA/CD Carrier Sense Multiple Access/Collision Detect CSN Communication Services Network CT Call Transfer CTCH Common Traffic Channel CW Call Waiting DCCH Dedicated Control Channel DCH Dedicated Channel DCS Digital Cellular Systems DES Digital Encryption Standard DHCP Dynamic Host Configuration Protocol DL Downlink DNS Domain Name Server DPCCH Dedicated Physical Control Channel DPCH Dedicated Physical Channel DPDCH Dedicated Physical Data Channel DRC Data Rate Control DRNC Drift Radio Network Controller DRNS Drift Radio Network Subsystem D-RNTI Drift RNTI DS Direct Spread DS-CDMA Direct-Sequence Code Division Multiple Access DSCH Downlink Shared Channel DSCP Differentiated Service Code Point DSL Digital Subscriber Line DSSS Direct Sequence Spread Spectrum DTCH Dedicated Traffic Channel DTX Discontinuous Transmission EIR Equipment Identification Register EACH Enhanced Access Channel E-AGCH E-DCH Absolute Grant Channel E-DCH Enhanced – Dedicated Channel EDGE Enhanced Data Rates for Global Evolution E-DPCCH E-DCH Dedicated Physical Control Channel E-DPDCH E-DCH Dedicated Physical Data Channel E-HICH E-DCH HARQ Acknowledgement Indicator Channel
Acronyms
B-6 Mastering HSDPA/HSUPA Signaling
E-TFC E-DCH Transport Format Combination E-TFCI Enhanced Dedicated Channel Transport Format Combination Identifier FACCH Fast Associated Control Channel FACH Forward Access Channel FCC Federal Communications Commission F-CCCH Forward Common Control CHannel FCCH Frequency-Correction Channel FCH Forward Control Channel FCH Frame Control Header FCS Frame Check Sequence FDD Frequency Division Duplex FDM Frequency Division Multiplexing FDMA Frequency Division Multiple Access F-DPCH Fractional Dedicated Physical Channel FEC Forward Error Correction FER Frame Error Rate FHSS Frequency Hopping Spread Spectrum FM Frequency Modulation FN Frame Number FP Frame Protocol FSK Frequency Shift Keying FTP File Transfer Protocol GERAN GSM EDGE Radio Access Network GGSN Gateway GPRS Support Node GI Guard Interval GLR Gateway Location Register GMM GPRS Mobility Management GMSC Gateway Mobile Switching Center GMSK Gaussian Minimum Shift Keying GPRS General Packet Radio Service GPS Global Positioning System GSM Global System for Mobile Communication GSN GPRS Support Node GT Guard Time GTP GPRS Tunneling Protocol GUI Graphical User Interface H-ARQ Hybrid ARQ HDR High Data Rate H-FDD Half-Frequency Division Duplex HLBS Highest Priority Logical Channel Buffer Status HLID Highest Priority Logical Channel ID HLR Home Location Register HO Handover HRPD High Rate Packet Data
Acronyms
Mastering HSDPA/HSUPA Signaling B-7
HSCSD High-Speed Circuit Switched Data HSDPA High Speed Downlink Packet Access HS-PDSCH High Speed Physical Downlink Shared Channel HSS Home Subscriber Server HTML Hyper Text Markup Language HTTP Hype Text Transfer Protocol H-RNTI High-Speed Radio Network Temporary Identifier HRPD High Rate Packet Data HSCSD High-Speed Circuit Switched Data HSDPA High Speed Downlink Packet Access HS-DPCCH High Speed – Dedicated Physical Control Channel HS-DSCH High Speed – Downlink Shared Channel HS-SCCH High Speed - Shared Control Channel HSS Home Subscriber Server HSUPA High Speed Uplink Packet Access ICI Inter-Carrier Interference IE Information Elements IEEE Institute of Electrical and Electronics Engineers IETF Internet Engineering Task Force IFFT Inverse Fast Fourier Transform IK Integrity Key IKE Internet Key Exchange IMEI International Mobile Equipment Identity IMS IP Multimedia Subsystem IMSI International Mobile Subscriber Identity IMT International Mobile Telecommunication IP Internet Protocol IPSec Internet Protocol Security Ipv4 Internet Protocol version 4 Ipv6 Internet Protocol version 6 IS Interim Standard ISDN Integrated Services Digital Network ISI Inter-Symbol Interference ISM Industrial Scientific Medical ISP Internet Service Provider ITU International Telecommunication Union IWF InterWorking Function kbps Kilobits per second L1 Layer 1 (physical layer) L2 Layer 2 (data link layer) L2CAP Link Level Control and Adaptation Protocol L3 Layer 3 (network layer) LAC Link Access Control LAC Location Area Code
Acronyms
B-8 Mastering HSDPA/HSUPA Signaling
LAI Location Area Identity LAN Local Area Network LAPB Link Access Procedure, Balanced LAPD Link Access Procedure for the D channel LOS Line of Sight LRN Location Routing Number LTU Logical Transport Unit MAC Medium Access Control MAH Mobile Access Hunting MAN Metropolitan Area Network MAP Mobile Access Protocol MAP Mobile Application Part MBMS Multimedia Broadcast Multicast Service MC Messaging Center MC MultiCarrier MCC Mobile Country Code MC-CDMA Multi-Carrier Code Division Multiple Access MCM Multi-Carrier Modulation MCS Modulation and Coding Scheme ME Mobile Equipment MEID Mobile Equipment Identifier MIME Multiple Internet Mail Extensions MIMO Multiple Input Multiple Output MIP Mobile IP MM Mobility Manager/Mobility Management MN Mobile Node MNC Mobile Network Code MN ID Mobile Node Identifier MOU Minutes of Use MS Mobile Station MSB Most Significant Bits MSC Mobile Switching Center MSI Mobile Session Identifier MSID Mobile Station Identifier MSS Mobile Subscriber Station MT Mobile Terminal Mux Multiplex NACK Negative ACK NAI Network Access Identifier N-AMPS Narrowband Advanced Mobile Phone System NAS Non-Access Stratum NAT Network Address Translation NBAP Node B Application Part NDI New Data Indicator
Acronyms
Mastering HSDPA/HSUPA Signaling B-9
NMSI National Mobile Station Identity NMT Nordic Mobile Telephone NNI Network to Network Interface NSAPI Network layer Service Access Point Identifier OA&M Operations, Administrations and Maintenance ODCH ODMA Dedicated Channel ODMA Opportunity Driven Multiple Access ODTCH ODMA Dedicated Traffic Channel OFDM Orthogonal Frequency Division Multiplexing OFDMA Orthogonal Frequency Division Multiplexing Access OMC Operations and Maintenance Centers OMC-R Operations Maintenance Center - Radio OMC-S Operations Maintenance Center - Switching OS Operating System OSI Open Systems Interconnection OSPF Open Shortest Path First OVSF Orthogonal Variable Spreading Factor P2MP Point-to-Multipoint P2P Point-to-Point PACCH Packet Associated Control Channel PAGCH Packet Access Grant Channel PAN Personal Area Network P-ARQ Packet ARQ PBCCH Packet Broadcast Control Channel PC Power Control PCB Power Control Bit PCCH Packet Common Control Channel PCCH Paging Control Channel PCF Packet Control Function PCH Paging Channel PCM Pulse Code Modulation PCPCH Physical Common Packet Channel PCS Personal Communication Services PCU Packet Control Unit PD Protocol Discriminator PDA Personal Digital Assistant PDC Personal Digital Cellular PDCCH Packet Dedicated Control Channel PDCH Packet Data Channel PDCP Packet Data Convergence Protocol PDN Packet Data Node PDP Packet Data Protocol PDSN Packet Data Serving Node PDTCH Packet Data Traffic Channel
Acronyms
B-10 Mastering HSDPA/HSUPA Signaling
PDU Protocol Data Unit PER Packet Error Rate PHY Physical Layer PIN Personal Identification Number PLMN Public Land Mobile Network PN Pseudo-random Noise PPCH Packet Paging Channel PPDN Public Packet Data Network PPM Pulse Position Modulation PPP P oint-to-Point Protocol PPTP Point-to-Point Tunneling Protocol PRACH Physical Random Access Channel PRI Primary Rate Interface PS Packet-Switched PSDU Protocol Service Data Unit PS-CN Packet Switched-Core Network PSK Phase Shift Keying PSTN Public Switched Telephone Network PTM Point to Multipoint PTP Point to Point P-TMSI Packet TMSI (Temporary Mobile Subscriber Identity) QAM Quadrature Amplitude Modulation QoS Quality of Service QPSK Quadrature Phase Shift Keying RA Routing Area RAB Radio Access Bearer RAC Routing Area Code RACH Random Access Channel RAI Routing Area Identity RAN Radio Access Network RANAP Radio Access Network Application Part RAND Random Number RARP Reverse Address Resolution Protocol RAT Radio Access Technology RATI Random Access Terminal Identifier RB Radio Bearer RBP Radio Burst Protocol REL Release Request RF Radio Frequency RLC Radio Link Control RLC Release Confirm RLP Radio Link Protocol RN Radio Network RNC Radio Network Controller
Acronyms
Mastering HSDPA/HSUPA Signaling B-11
RNS Radio Network Subsystem RNSAP Radio Network Subsystem Application Part RNTI Radio Network Temporary Identity RRC Radio Resource Control RRI Reverse Rate Indicator RRP Registration Reply RRQ Registration Request RSCP Received Signal Code Power RSN Retransmission Sequence Number Rsp Response SAAL Signaling ATM Adaptation Layer SAC Service Area Code SAC Subscriber Access Channel SACCH Slow Associated Control Channel SAP Service Access Point SAPI Service Access Point Identifier SAR Segmentation and Reassembly Sublayer SC Single Carrier SCCH Supplemental Code Channel SCCP Signaling Connection Control Part SCH Synchronization Channel SDCCH Standalone Dedicated Control Channel SDLC Synchronous Data Link Control SDU Service Data Unit SGSN Serving GPRS Support Node SIB System Independent Building Blocks/System Information Block SID System Identifier SIM Subscriber Identity Module SMS Short Message Service SM-SC Short Message Service Center SMS-GMSC Short Message Service-Gateway MSC SMS-IWMSC Short Message Service-Interworking MSC SMTP Simple Mail Transfer Protocol SN Service Node SNR Signal to Noise Ratio SRNC Serving Radio Network Controller SRNS Serving RNS SS Subscriber Station SS7 Signaling System 7 S-SCM Serving SCM SSD Shared Secret Data SSN Sub System Number SSP Service Switching Point STC Space Time Coding
Acronyms
B-12 Mastering HSDPA/HSUPA Signaling
TB Transport Blocks TBF Temporary Block Flow TC Transport Channel TCAP Transaction Capabilities Application Part TCH Traffic Channel TCH/FS Traffic Channel/Full Rate Speech TCH/HS Traffic Channel/Half Rate Speech TCP Transmission Control Protocol TCP/IP Transmission Control Protocol/Internet Protocol TCS BIN Telephony Control Specification-Binary TD Transmit Diversity TDD Time Division Duplex TDM Time Division Multiplex(ing) TDMA Time Division Multiple Access TE Terminal Equipment TEBS Total E-DCH Buffer Status TEID Tunnel Endpoint Identifier TF Transport Format TFCI Transport Format Combination Indicator TFCS Transport Format Combination Set TFI Transport Format Identifier TFS Transport Format Set TI Transaction Identifier TID Tunnel Identifier TM Traffic Mode TM Transparent Mode TMSI Temporary Mobile Subscriber Identity TP Transmission Protocol TRAU Transcoder and Rate Adaptor Unit TRN Temporary Routing Number TTA Telecommunication Technology Association UARFCN UMTS Absolute Radio Frequency Channel Number UDP User Datagram Protocol UE User Equipment UI User Interface UL Uplink UM Unacknowledged Mode UMTS Universal Mobile Telecommunications System URA User Registration Area URL Uniform Resource Locator U-RNTI UTRAN Radio Network Temporary Identity USIM UMTS Subscriber Identity Module UTRA UMTS Terrestrial Radio Access UTRAN UMTS Terrestrial Radio Access Network
Acronyms
Mastering HSDPA/HSUPA Signaling B-13
VLR Visitor Location Register VoIP Voice over Internet Protocol VPN Virtual Private Network WLAN Wireless Local Area Networks WLL Wireless Local Loop WPD Wireless Packet Data WSP Wireless Service Provider WWW World Wide Web
References
Mastering HSDPA/HSUPA Signaling C-1
References
References
C-2 Mastering HSDPA/HSUPA Signaling
References
Mastering HSDPA/HSUPA Signaling C-3
References
Standards 1. 3GPP TS 23.002: “Network architecture” 2. 3GPP TS 23.003: “Numbering, addressing and identification” 3. 3GPP TS 23.060: “General Packet Radio Service (GPRS); Service description; Stage 2” 4. 3GPP TS 23.107: “Quality of Service (QoS) concept and architecture” 5. 3GPP TS 23.107: “Non-Access-Stratum (NAS) functions related to Mobile Station (MS) in idle
mode” 6. 3GPP TS 23.930: “Iu principles” 7. 3GPP TS 24.008: “Mobile radio interface Layer 3 specification; Core network protocols; Stage 3” 8. 3GPP TS 25.133: “Requirements for support of radio resource management (FDD) ” 9. 3GPP TS 25.301: “Radio Interface Protocol Architecture” 10. 3GPP TS 25.302: “Services provided by the physical layer” 11. 3GPP TS 25.304: “User Equipment (UE) procedures in idle mode
and procedures for cell reselection in connected mode” 12. 3GPP TS 25.308: “High Speed Downlink Packet Access (HSDPA),Overall description” 13. 3GPP TS 25.309: “FDD Enhanced Uplink, Overall description ” 14. 3GPP TS 25.321: “Medium Access Control (MAC) Protocol Specification” 15. 3GPP TS 25.322: “Radio Link Control (RLC) Protocol Specification” 16. 3GPP TS 25.323: “Packet Data Convergence Protocol (PDCP) specification” 17. 3GPP TS 25.331: “Radio Resource Control (RRC) Protocol Specification” 18. 3GPP TS 25.410: “UTRAN Iu Interface : General Aspects and Principles” 19. 3GPP TS 25.413: “UTRAN Iu Interface RANAP signaling” 20. 3GPP TS 25.420: “UTRAN Iur Interface: General Aspects and Principles” 21. 3GPP TS 25.423: “UTRAN Iur interface Radio Network Subsystem Application Part
(RNSAP)signaling” 22. 3GPP TS 25.425: “UTRAN Iur interface user plane protocols for Common Transport Channel,
data streams” 23. 3GPP TS 25.427: “UTRAN Iur/Iub interface user plane protocol for DCH data streams” 24. 3GPP TS 25.430: “UTRAN Iub Interface: General Aspects and Principles” 25. 3GPP TS 25.433: “UTRAN Iub interface NBAP signaling” 26. 3GPP TS 25.435: “UTRAN Iub interface user plane protocols for CCH data streams” 27. 3GPP TS 25.808: “FDD enhanced uplink; Physical layer aspects” 28. 3GPP TS 25.858: “Physical layer aspects of UTRA High Speed Downlink Packet Access” 29. 3GPP TS 25.832: “Manifestations of Handover and SRNS relocation” 30. 3GPP TS 25.851: “RAB Quality of Service (QoS) Renegotiation over Iu” 31. 3GPP TS 48.018: “BSS GPRS Protocol (BSSGP) 32. 3GPP TS 25.901: “Network Assisted Cell Change (NACC) from UTRAN to GERAN; Network Side
Aspects”
References
C-4 Mastering HSDPA/HSUPA Signaling
33. 3GPP TS 25.922: “Radio resource management strategies” 34. 3GPP TS 25.931: “UTRAN Functions, examples on signaling procedures” 35. 3GPP TS 29.060: “General Packet Radio Service (GPRS); GPRS Tunneling Protocol (GTP) across
the Gn and Gp interface 36. 3GPP TS 33.102: “3G security; Security architecture” 37. 3GPP TS 43.022: “Functions related to Mobile Station (MS) in idle mode and group receive mode 38. 3GPP TS 44.060: “General Packet Radio Service (GPRS),Mobile Station (MS) - Base Station
System (BSS) interface” 39. 3GPP TS 44.118: “Mobile radio interface layer 3 specification, Radio Resource Control (RRC)
protocol, Iu Mode” UMTS Forum Technical Reports 1. A Regulatory Framework for UMTS 2. The Path towards UMTS – Technologies for the Information Society Web Sites 1. Third Generation Partnership Project (3GPP) Homepage – www.3GPP .org 2. European Telecommunications Standards Institute – www.etsi.org 3. UMTS Forum – www.umts-forum.org 4. ITU web site for IMT-2000 - www.itu.int/imt 5. Telecommunication Industries Association – www.tiaonline.org 6. Universal Wireless Communications Consortiums – www.uwcc.org 7. Association of Radio Businesses and Industries (Japan) –
www.arib.or.jp/arib/english/index.html 8. Telecommunication Technologies Association (Korea)– www.tta.or.kr/e_frame4.html 9. CDMA Development Group – www.cdg.org 10. Ericsson web site – www.ericsson.com/wcdma