V7.4 NORTEL NETWORKS CONFIDENTIAL CDMA 2000 1xEV-DO System Overview Course # 0890AEN Version 01.02

V7.4 NORTEL NETWORKS CONFIDENTIAL

CDMA 2000 1xEV-DO System Overview

Course # 0890AEN

Version 01.02

NORTEL NETWORKS CONFIDENTIAL 2

OBJECTIVES

This class is intended for anyone requiring an introduction to 1x EV-DO.

At the conclusion of this class the student will be able to discuss:

Nortel Networks implementation of 1x EV-DO

New equipment added to the network and its functionality

Theory of IS-856

Basic call flow


What is CDMA2000 1xEV-DO?

• CDMA2000 1xEV-DO stands for 1xRTT Evolution – Data Only—What this means is that it is an evolution from

CDMA2000 1X (IS-2000/CDMA2000) networks—Where CDMA2000 1X has both data and voice

capabilities, CDMA2000 1xEV-DO is data only (without the voice component)

• CDMA2000 1xEV-DO offers high-speed packet data rates up to 2.45 Mbps where CDMA2000 1X has a maximum data rate of 153.6 Kbps


What is CDMA2000 1xEV-DO? (continued)

• CDMA2000 1xEV-DO is overlaid on an existing CDMA2000 1X network but requires a separate 1.25 MHz carrier and a dedicated T1/E1 backhaul from the Metro Cell to the data only radio network controller (DO-RNC)

• Shares the packet-data network with CDMA2000 1X

• CDMA2000 1xEV-DO is based on IS-856 / CDMA2000 1X is based on IS-2000


CDMA2000 1xEV-DO components

• As CDMA2000 1xEV-DO is overlaid on an existing CDMA2000 1X network, there are many shared components

• The shared components with CDMA2000 1X are:— MetroCell— PDSN— AAA server (if not deploying AN-AAA)


CDMA2000 1xEV-DO components (continued)

• The new components required for CDMA2000

1xEV-DO are:—Data Only Module (DOM) located in the MetroCell—Data Only Radio Network Controller (DO-RNC)

located at the central office (CO)—Data only element management subsystem

(DO-EMS) and can be co-located at the CO with the DO-RNC and BSC

—Access network authorization, authentication and accounting (AN-AAA) server (optional)


CDMA2000 1xEV-DO components (continued)Data Only Module (DOM)

• IS-856 module added to CEM shelf in Metro Cell

• provides CDMA2000 1xEV-DO modem capability.

• performs all the encoding/decoding of the IP packets

• Requires MFRM

• supports 30 connected sessions per sector



Data Only Radio Network Controller (DO-RNC)

• at the core of the CDMA2000 1xEV-DO network

• manages the access terminal state, handoffs and connections to the packet data network through the packet data switching node (PDSN).

• controlling the DOMs at multiple cell sites over an IP-based backhaul network


CDMA2000 1xEV-DO components (continued)Data only element management

subsystem (DO-EMS)

• provides OA&M capability and controls the operation, administration, maintenance and provisioning (OAMP) operations for the CDMA2000 1xEV-DO radio access network (RAN).

• based on a Sun Netra 20 NEBS compliant platform and may be located at the central office (CO)

• stand-alone platform for performing OAM&P functionality within the CDMA2000 1xEV-DO network only

Sun Netra 20

Sun StorEdge 3310

Sun Blade 150



Access network authorization, authentication and accounting (AN-AAA) server

• optional requirement (as specified in IS-878) used for access terminal authentication at the beginning of a CDMA2000 1xEV-DO data session

• used for device level authentication

• terminates the point-to-point protocol (PPP) session required for terminal authentication at the beginning of a CDMA2000 1xEV-DO session



Network upgrades from CDMA2000 1X

• Dedicated T1/E1 backhaul from the Metro Cell to the DO-RNC

• Additional 1.25 MHz carrier for data only traffic

Note: More 1.25 carriers can be added for increased users (additional DOMs need to be added for each additional CDMA2000 1xEV-DO carrier)


Lesson 2:

The evolution to CDMA2000 1xEV-DO


The evolution to CDMA2000 1xEV-DO


The path to CDMA2000 1xEV-DO

CDMA2000 1X in the beginning:• CDMA2000 1xEV-DO is an

evolution from conventional IS-2000 (CDMA2000 1X) networks.

• CDMA2000 1X offers both voice and data capabilities compared to conventional CDMA (IS-95) networks (voice only)

• CDMA2000 1X high speed packet data

— Rates of up to 153.6 Kbps (144 Kbps user)

• New hardware for 3G (CDMA2000 1X):

— XCEM in Metro Cell— SCI-S and ESEL in BSC— Shasta BSN 5000 for PDSN

and HA functionality— AAA server, routers, hubs, for

data network administration


The path to CDMA2000 1xEV-DO (continued)

Evolution to CDMA2000 1xEV-DO:• CDMA2000 1xEV-DO offers data

only capabilities compared to 1xRTT networks (voice and data)

• CDMA2000 1xEV-DO overlaid on existing CDMA2000 1x network and shares the following:

— Metrocell— PDSN— AAA server (if present)

• New components for CDMA2000 1xEV-DO

— data only module (DOM)— data only radio network

controller (DO-RNC)— data only element

management subsystem(DO-EMS)



CDMA2000 1xEV-DO offers:

• High speed packet data

— Rates of up to 2.45 Mbps

• Full time forward power by time division multiplexing

• No shared spectrum with other users

• No soft hand-offs in forward direction, soft hand-off in reverse



Packet Data Network

The CDMA2000 1xEV-DO system does not define a new packet data network architecture.

In fact, both the CDMA2000 1xEV-DO and the CDMA2000 1X systems share the same packet data network infrastructure.


Lesson 3:

What is CDMA20001xEV-DO?


What is CDMA2000 1xEV-DO?

• CDMA2000 1xEV-DO (1xRTT evolution–data only) is a wireless packet data-only technology—Used for customer data applications where voice communication

is not required

• high-speed packet data support of variable rates up to 2.45 Mbps on the forward link and up to 153.6 kbps on the reverse (upload) link

• CDMA2000 1xEV-DO uses time-division multiplexing (TDM) in the forward direction, meaning there are no soft handoffs in the forward direction and only one terminal receives data from each sector at a given time


Benefits of CDMA2000 1xEV-DO

• Uses less bandwidth that UMTS (1.25 MHz rather that 5 MHz)

• Core network elements are shared with CDMA2000 1X meaning cost of upgrade is minimal

• No degradation of CDMA2000 1X voice calls since CDMA2000 1xEV-DO is deployed on separate 1.25 MHz carriers

• As CDMA2000 1xEV-DO uses TDM, there is full time full power as the bandwidth is not shared with other users like CDMA2000 1X


Data only element management subsystem (DO-EMS) and client

DO-EMS Client

web-based client runs in standard web browsers, offering network administrators a familiar, easy-to-use interface to robust configuration, fault, and performance management tools

Provides:

• Network topology views

• Network database views

• Active device panel

• Performance statistics administration

• System administration


Data only element management subsystem (DO-EMS) and client (continued)

DO-EMS Client (continued)

Provides

• Fault management tools— alarm browser— event browser

• Management tools— MIB manager— Policy manager



The access network authorization, authentication and accounting (AN-AAA) server is an optional requirement (as specified in IS-878) used for access terminal authentication at the beginning of a CDMA2000 1xEV-DO data session.

If operators do not deploy an AN-AAA, they may use the existing AAA Radius server currently used in the CDMA2000 1X network.



With an AN-AAA:

• The DO-RNC authenticates access terminals.

• The DO-RNC communicates with one or more AN-AAA servers.

• The AN-AAA can act as a proxy server to determine the Radius server for an access terminal that is roaming.



Benefits of deploying AN-AAA

• Consistent IMSI (International Mobile Subscriber Identity) for billing

• Control of authentication

• PDSN protection

• Theft of 1xEV-DO access


Hybrid access terminal

A new hybrid access terminal is required to support voice on IS-2000 systems and packet data services on both IS-2000 and IS-856 systems. The hybrid access terminal is required to operate in both IS-856 and IS-2000 modes and is capable of monitoring both the CDMA2000 1xEV-DO and CDMA2000 1X systems simultaneously.


Lesson 4:

Introduction to IS-856


Introduction to IS-856

The TIA/EIA Engineering Committee TR-45 (Mobile and Personal Communications Systems) has developed a standard called IS-856 as a companion to the already existing IS-2000 standard. These standards are the next generation of wireless standards after the second-generation (2G) CDMA standards, known as IS-95.

The IS-856 (CDMA2000 1xEV-DO) air interface standard provides high rate packet data services between the access terminal and the access network.


IS-856 Protocol Layers

The CDMA2000 1xEV-DO protocol layering does not conform to the open system interconnection (OSI) seven layer model.

OSI seven layer protocol IS-856 seven layer protocol

Layer 7: Application layer Layer 7: Application layer

Layer 6: Presentation layer Layer 6: Stream layer

Layer 5: Session layer Layer 5: Session layer

Layer 4: Transport layer Layer 4: Connection layer

Layer 3: Network layer Layer 3: Security layer

Layer 2: Data Link Layer Layer 2: MAC layer

Layer 1: Physical layer Layer 1: Physical layer



The CDMA2000 1xEV-DO air interface protocol layers (continued)

IS-856 seven layer protocol

Description

Layer 7: Application layer Message routing, RLP, flow control

Layer 6: Stream layer Multiplex various application streams

Layer 5: Session layer Establishes/configures data sessions

Layer 4: Connection layer Establishes and manages radio connection

Layer 3: Security layer Authentication and encryption

Layer 2: MAC layer Data rate controlling and scheduling

Layer 1: Physical layer Adaptive modulation and code spreading



The CDMA2000 1xEV-DO air interface protocol layers

IS-856 seven layer protocol

Description

Layer 7: Application layer Message routing, RLP, flow control

Layer 6: Stream layer Multiplex various application streams

Layer 5: Session layer Establishes/configures data sessions

Layer 4: Connection layer Establishes and manages radio connection

Layer 3: Security layer Authentication and encryption

Layer 2: MAC layer Data rate controlling and scheduling

Layer 1: Physical layer Adaptive modulation and code spreading


Theory of operations

RF PHY

RF PHY

Layer 2

Layer 1

Ethernet Ethernet Ethernet

100BaseT 100BaseT 100BaseT

MAC

IP IP IP IP

GRE A10/A11

GRE A10/A11

GRE GRE

Abis Abis

MAC

RLP RLP

PPP PPP

AT Metro Cell (DOM) DO-RNC PDSN


IS-856 Physical Layer

Major improvements to the physical layer from IS-2000:— Higher data rates : utilizes

turbo coding in forward and reverse directions

— Dynamic turbo encoding rates : Turbo codes have been shown to perform better for high rate data services

— Source identification : no source identification in reverse direction

— Higher order modulation : adaptive modulation


IS-856 Physical Layer (continued)

Major improvements to the physical layer from IS-2000:

— Channelization : forward link channels time-multiplexed (no Walsh codes) not code multiplexed

— Each access terminal receives full power for their time rather than sharing power across time


IS-856 Physical Layer (continued)

Major improvements to the physical layer from IS-2000:

— Forward link transmit power : transmits at maximum available power all the time

— IS-856 channel structure : forward direction = time division multiplexed, reverse direction = code division multiplexed


IS-856 Forward link

Forward traffic flow travels from the packet data network/internet through the CDMA2000 1xEV-DO radio access network to the user.


IS-856 Forward link

Forward channel structure

• The access network transmits the following forward link channels at full power in time-multiplexed fashion. At a fixed position in every physical layer slot, these channels are transmitted:

— pilot channel

— medium access control

— control channel

— traffic channel


IS-856 Forward link

Forward channel slot structure

In forward direction, there are two types of slots:

• Active Slot: When access network has either control information or user traffic to send, it sends this information along with MAC and pilot channel in a time-multiplexed fashion.

• Idle Slot: When access network does not have control information or user traffic to send, it still sends pilot and MAC channels in their given time at full power and does not transmit control/traffic information.


IS-856 Forward link

Paging/control channel slot structure

• access terminal (handset) monitors both the CDMA2000 1xEV-DO and CDMA2000 1X network simultaneously

• Paging channels for both CDMA2000 1xEV-DO and CDMA2000 1X are staggered

• If paging channels collide, IS-856 assigns a different paging slot


IS-856 Forward link

Forward frame structure

• Physical layer code spread across 1.25 MHz – identical to IS-95/2000

• IS-856 only has one physical channel and MAC, control and traffic channels are time multiplexed on the single channel


IS-856 Forward link

Fat pipe scheduling

• using a large radio spectrum as a shared wireless link

• all terminals in sector share wireless link

• access network schedules transmission of packets over shared link

• packets are time division multiplexed not code multiplexed


Forward Traffic Channel Physical Layer

ENCODER 1/3 OR 1/5

SCRAMBLER

SYMBOLPUNCTURING

CHANNEL INTERLEAVER

MODULATORQPSK8PSK

16QAM

DEMUX

16-ARYWALSHCOVER

WALSHGAIN

1/4

TDM

WALSHCHIP

SUMMER

I

Q

I

Q


DATA RATE IN KBS 38.4 76.8 153.6 307.2 307.2 614.4 614.4 921.6 1288.8 1288.8 1843.2 2457.6

# BITS PER PACKET 1024 1024 1024 1024 2048 1024 2048 3072 2048 4096 2048 4096

MODULATION QPSK

QPSK

QPSK

QPSK

QPSK

QPSK

QPSK

8PSK QPSK 16QAM

8PSK 16QAM

CODING RATE 1/5 1/5 1/5 1/5 1/3 1/5 1/3 1/3 1/3 1/3 1/3 1/3

# OF SLOTS 16 8 4 2 4 1 2 2 1 2 1 1

# chips Preamble Pilot

10243072

5121536

256768

128384

128768

64192

64384

64384

64384

64384

64192

64192

# chips MAC 4096 2048 1024 512 1024 256 512 512 512 512 256 256

# chips DATA 24,576

12,288

6144 3072 6272 1536 3136 1536 3136 3136 1536 1536

FORWARD CHANNEL MODULATION


IS-856 Reverse link

Reverse traffic flow travels from the user through the CDMA2000 1xEV-DO radio access network to the packet data network/internet .


IS-856 Reverse Link

• reverse link of IS-856 is quite similar to the reverse link in an IS-2000 system

• reverse link power control performed same asIS-2000 (except at 600 times per second)

• access network sends power control command in every slot for all connected ATs


IS-856 Reverse Link

• IS-856 and IS-2000 similarities— power control and soft handoff supported— BPSK modulation on I & Q (data & pilot) carrier to reduce

peak to average ratio— distinct user PN sequence for source ID— data rates from 9.6 to 153.6 Kbit/s— transmits pilot and data channels


IS-856 Reverse Link

• IS-856 only operations

— transmits MAC and ACK channels

— MAC information

— reverse rate indicator (RRI)

— data rate control (DRC)


IS-856 Reverse Link

Reverse channel structure

In the reverse direction, the access terminal can use access or traffic channel— access and traffic

channels are code multiplexed

Access channel mode:— access terminal is idle and

transmits pilot and data channels

Traffic channel:— access terminal

is connected and transmits MAC, data, pilot and ACK channels


IS-856 Reverse Link

Reverse channel usage

• Once connected, the access terminal is either in idle or connected state

• idle: monitors forward control channel

• connected: monitors forward traffic and control channels


IS-856 Reverse Link

Access channel

• consisting of a pilot and data channel

• used by the access terminal to initiate communication with the access network

• respond to an access terminal directed message

• access terminal sends a series of access probes (preamble followed by one or more access channel physical layer packets) until it receives a response from the access network access probe consists of a preamble followed by one or more access channel

• During preamble only pilot channel is transmitted

• During the access channel physical layer packet transmission, both the pilot channel and the data channel are transmitted

• physical layer packets transmitted at fixed data rate of 9.6 Kbps


IS-856 Reverse Link

Reverse traffic channel

• comprised of pilot, MAC, ACK and data channels

• On the pilot channel, reverse rate indicator bits are time-multiplexed with the pilot bits

• ACK channel protected with repetition followed by spreading with 8-bit Walsh code W4

• data rate control (DRC) bits encoded and repeated for proper data protection.


IS-856 Reverse Link

• Reverse rate indicator

The reverse rate indicator (RRI) channel is used by the access terminal to indicate the data rate at which the data channel is transmitted.

• Reverse ACK channel

In the CDMA2000 1xEV-DO system, acknowledgment is provided at the physical layer. This provides quick response from the receiver (access terminal) to the transmitter (access network).


IS-856 Reverse Link

Data rate control (DRC)• DRC channel in the reverse traffic

channel is used to indicate the selected serving sector and the requested data rate on the forward traffic channel

Reverse link parameters• access terminal selects a data rate

and sends the data traffic at the selected rate on the reverse traffic channel and it also sends reverse rate indicator (RRI) in time division multiplexed fashion with the pilot channel

Reverse link power control• the power control command is

repeated four times and sent in the MAC channel


IS-856 Reverse Link

Medium access control (MAC) layer

• responsible for determining scheduling and transmission policies

• MAC layer determines the best possible data rate on slot-by-slot basis in both directions

• physical layer is responsible for actual transmission procedures based on input from MAC layer


DATA RATE (kbps) 9.6 19.2 38.4 76.8 153.6

RATE INDEX 1 2 3 4 5

Bits per packet 256 512 1024 2048 4096

Packet duration (ms) 26.66 26.66 26.66 26.66 26.66

Code rate ¼ ¼ ¼ ¼ ½

Code Symbols per packet 1024 2048 4096 8192 8192

Symbol rate (KSPS) 38.4 76.8 153.6 307.2 307.2

Packet repeats 8 4 2 1 1

Mod symbol rate (KSPS) 307.2 307.2 307.2 307.2 307.2

Modulation BPSK BPSK BPSK BPSK BPSK

PN CHIPS per packet bit 128 64 32 16 8

REVERSE CHANNEL MODULATION


IS-856 Medium access control

Medium access control (MAC) functions

• Forward direction— Scheduling transmission

for different access terminals based on input given by these terminals

— handles scheduling transmission for forward control channel and forward traffic channel

— responsible for providing input to access terminals on the reverse link so that the access terminal can adjust reverse link data rates.



Medium access control (MAC) functions

• Reverse direction— handles transmission and

reception on access and traffic channel

— provides input to the access network on what is the best data rate and best sector based on the existing channel conditions.

— responsible for best possible data for transmission on the reverse link



Medium access control (MAC) protocols

Each protocol defines procedures and messages for handling of one and only one channel.

• access channel protocol

• control channel MAC protocol

• forward traffic channel MAC protocol

• reverse traffic channel MAC protocol



Medium access control (MAC) states

• The FTC-MAC can be in one of the three states when the access terminal is activated. The various states are described briefly here:— inactive state: when the access

terminal is not assigned a forward traffic channel (not connected)

— variable rate state: when access terminal is assigned a forward traffic channel (connected)

— fixed rate state: the access terminal always receives traffic from one particular sector in its active set at a fixed rate



Medium access control (MAC) schedulers

• Schedulers handle how data gets transmitted to the access terminals.

• Goal is to improve overall system throughput

• Bandwidth allocated to different access terminals based on reported data rates

• For 1xEV-DO, there are four different schedulers available:— round-robin— best rate— equal opportunity— proportional fairness




Round robin schedulers

• utilize first in, first out strategy

• Each request gets put into a queue and when it is at the top of the queue it receives the resource allocation requested.




Best rate schedulers

• goals are to process the requests in the buffer with the highest data rates first

• high system throughput since the highest requested data rates always get scheduled

• drawback is that users with low data rates can be withheld resources in favor of those with high data rates.




Equal opportunity scheduler

• Each user request is tracked in the buffer and the user with the lowest data rate receives the resource allocation requested.

• The disadvantage of this is that the overall throughput may be low especially if there are many low data rate users.

• Users with high data rates may be withheld resources since the lowest data rate users are processed first.




Proportional fairness scheduler

• The goal is to provide fairness to each user regardless of their data rates.

• The scheduler maintains a moving average of DRC (data rate control) values and the scheduler transmits data to the access terminal only when the DRC value is greater than or equal to the moving average.

• This increases overall throughput for individual users as well as the whole system.


Lesson 5:




Evolving to CDMA2000 1xEV-DO

• Goals of CDMA2000 1xEV-DO— provide efficient packet-based air interface— Sharing components with CDMA 1X— Reduced cost of ownership



Evolving to CDMA2000 1xEV-DO (continued)

• IP network access

CDMA2000 1xEV-DO and CDMA2000 1X systems share the same packet data network infrastructure

• Packet data model—mobile switching center (MSC/MTX) and home location

registry (HLR) no longer required—MSC/MTX, HLR are responsible for radio access

authentication and authorization functions not data functions —packet data service authentication comes from a AAA (or

AN-AAA) server



Evolving to CDMA2000 1xEV-DO

• Packet data calls in CDMA2000 1xEV-DO

The CDMA20001xEV-DO networks support the same two IP addressing options for packet data as CDMA2000 1X networks:

— simple IP

— mobile IP



Handoffs

• IS-856 does not support soft handoffs in the forward link

• IS-95/2000 supports soft handoffs in the forward link

• IS-856 supports soft handoff In the reverse link similar toIS-95 and IS-2000



Time-division multiplexing

• TDM used in forward direction

• Each user given dedicated time slot on entire 1.25 MHz carrier for their period of time

• Within each slot, spread spectrum processing is used

• TDM removes inefficiencies (overhead) of power control and soft handoff


Theory of operationsFixed power variable rate

The CDMA2000 1xEV-DO system based on fixed power variable rate

• sector transmits at full power to every access terminal

• data rate varies depending on the interference experienced by the access terminal

• access terminal reports receivable data rates based on interference conditions for every scheduling period

• network transmits to the access terminal at that rate during that period

• The time slot and data rate for each connected user is adaptively determined by the scheduler so as to enhance CDMA2000 1xEV-DO aggregate forward data throughput


Appendix A:

Call processing


1X EV-DO Basic Call Processing

This section will cover different call processing scenarios including:

• Registration

• Call Flow

• Handoffs—DOM to DOM—DOM to 1X—1X to 1xEV-DO

NORTEL NETWORKS CONFIDENTIAL


Access Terminal Registration


Access terminal call origination


PDSN call origination


Handoff DOM to DOM


Handoff DOM to 1X system


Handoff 1X to 1X EV-DO System

Documents

V7.4 NORTEL NETWORKS CONFIDENTIAL CDMA 2000 1xEV-DO System Overview Course # 0890AEN Version 01.02