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Munish Chhabra - Aricent November 2013 LTE-A Challenges and Evolving LTE Network Architecture Mobile and Cloud Infrastructure Convergence

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Munish Chhabra - Aricent November 2013

LTE-A Challenges and Evolving LTE Network Architecture Mobile and Cloud Infrastructure Convergence

LTE-Advanced and HetNets

Challenges

Evolving LTE Network Architectures

Summary

Agenda

2 Proprietary & Confidential. ©Aricent Group 2013

LTE A & HetNets

3

Challenges….

Necessity to achieve desired capacity

Bring network closer to the user

More radio links, more antennas, higher spectral efficiency

LTE Advanced + HetNets -> Take capacity gains to the next level

Network Densification

5

First Step: Coverage (Macros) Next Step: Capacity (HetNets)

But, More Base Stations lead to … More Capex

• Equipment (baseband, radio, antennas) at each site

• Shelter, Air Conditioning, Battery at each site

• Backhaul – Connectivity with core network (cost vs performance)

Increased Opex

• More Rental and running cost

• More trained staff for network planning and maintenence

• More site visits for preventive and fault handling

• Energy Efficiency

• Significant part of OPEX

• Included Market, regulatory and customer requirements (especially for small cells)

Interoperability

Interworking nodes between different networks

Network Densification (Contd…)

6

A tier-1 operator in Europe typically spends around 60% of revenue in OPEX. The burden will surely increase

with LTE and LTE-A

The number of network nodes go-up exponentially

Besides they co-exist with multiple other RATs

Extremely challenging to maintain and optimize such networks e.g.

• # Neighbor Relationships grow exponentially

• # Handover Relationships grow exponentially

• Coverage / Capacity trade-offs between different network layers

• Interference management becomes even more challenging

• Dynamic traffic patterns and low base station utilization

• Residential areas in the evening, Commercial during the day

Network Manageability

7

Increasing radio network complexity casts its shadow on the backhaul

More base stations, more backhaul links

Base stations differ in terms of capacity, reach, transmission power and

radio access network technology, including 3G, “4G” and Wi-Fi

• Puts additional complexity burden on backhaul

ICIC and CoMP (Coordinated Multipoint) – Needed for better user

experience at cell edge

• ICIC – Coordination of spectrum allocation across multiple cells

• CoMP - Multiple base stations simultaneously serve a user device

• Needed - Real time co-ordination between base stations

• Needed - Low latency on backhaul

Base station need sub-frame level co-ordination

• Clocks need to be in phase

• Common reference needed from backhaul

The Backhaul Challenge

8

Carrier Aggregation

UE to handle multiple simultaneous transcievers

Contiguous and non-contiguous carriers may be aggregated

Challenging radio environment

MIMO

Up to 8 transmitters in DL

MIMO increases the number of system antennas

Design of

• Radio antennas supporting Multiband and MIMO

• In the tiny space on a UE

• Becomes extremely challengig

Battery life of devices

User Device Challenge

9

Higher base station density, more Interference

Randomly distributed

• Difficult to control and maintain coverage area, tilt, power and placement of

small form factor base stations

Particularly difficult to optimize Cell Edge users performance

• Terminal assigned to macro, sees strong interference from micro

• Especially if micro serves a CSG and the UE is not allowed to latch on to it

Interference Management

10

Almost ubiquitous availability of WiFi (especially indoors in homes and

offices) mandates it for operators to consider offload

Offload however comes with its own challenges that have no answer in

the specifications yet

• Pre-mature WiFi selection

• Improper choices

• Degraded QoS after movement to WiFi

• Managing Trusted/Non-trusted networks

• Ping-pong problem

WiFi and Offload Considerations

11

Evolving LTE Network Architectures

SDN would mean Network virtualization - Implementing more in software and using commoditized IT hardware

Programmability - The ability to centrally change traffic flows, partition the networks and

provide application-level QoS.

Separation of control and data plane

Telco SDN – The Next Wave

13

A network of point-to-

point connections

A programmable fabric that can be

manipulated in real time to meet the

needs of the applications and systems

that sit on top of it

Mobile Networks Now

SDN

Mobile Networks Then

Source: Telco2.net

SDN Example

14

Ref: Flexerasoftware.com

Separates the computing intensive baseband processing from the remote

radio deployments

Baseband processing is pooled at a semi-centralized location

C-RAN Enables

• Use of commodity HW to run baseband processing tasks

• More fluid resource allocation.

• Enables new feature implementation like CoMP and eICIC

• Helps ease capacity crunch by placing radios closer to the user

Cloud RAN – Specific SDN use-case for the RAN

15

Cloud RAN – The first implementation of virtualization in RAN layer

Cloud RAN – Architecture Possibilities

16

Active

Antenna

System

Remote

Radio

Head

Macro

Site

Centralized

Baseband

Bank

•2G/2.5 G

•UMTS

•HSPA

•LTE eNB

•LTE-A

Femto

Cells/

Wi-Fi

SON Server

RAN SERVERS

•GSM/GPRS

•UMTS

•UMTS Femto GW

•HeNBGW

•Wi Fi Access Gateway

Core Network

Internet

• Services are provided through optimum access technology

• Resources and coverage of a geographical area can be changed

dynamically

• SON can be used to get information for providing the necessary

configuration

• Resources are aggregated and dynamically allocated

• Reconfigurable BSs and controllers to support multiple Radio Access

technologies

IMS/

Operator Services

Optical

Coax

Controllers

on the

cloud

IP IP

Common

Management

Server

IP IP

ENodeB Framework

• RAN on the Cloud will need to cater to variable

capacity requirements and host multiple cells.

Aricent Layer 3 and Layer 2 including Scheduler,

MAC, RLC, PDCP, GTPU, are scalable for multi-

core architectures, supports multiple form-factors

(femto, pico,micro) and different capacity

requirements based on deployment.

• Single instance of Aricent Layer 3 can handle

multiple cells/sectors hosted on Cloud RAN

equipment and can interface with cells/sectors

hosted on other Cloud RAN equipment on X2

link.

• Aricent Layer 2 can handle one cell/sector per

instance and multiple instances of Layer 2 can be

utilized to handle multiple cells/sectors.

Aricent eNB IPR Readiness for C-RAN Solution

18

PDCP,

RLC,MA

C

Schedul

er GTPU

RRC,S1-AP,X2-AP

OAM & SON

Client RRM

Cloud Ready Aricent EPC Framework

19

EPC Frameworks

Multi-tenant solution

Scalable deployments

EPC on virtualized environment

Cloud Enablers

Router

Top of Rack

Switch

Top of Rack

Switch

eNodeBs

MMEs SGWs

PGWs

HSS PCRFs

Subnet 2

ISP 2

Integrated software offerings for MME,

Serving GW, PDN GW, HSS and

PCRF nodes for OEMs developing

cloud EPC solutions – running in

clusters across virtualized hardware

with separated routing tables Subnet 1

The promise of SDN and C-RAN: Mobile and Cloud Infrastructure Convergence

Significant improvements in the manageability and flexibility of the network

Prevent the networks from becoming prohibitively expensive to deploy

Easy scalability

Helps in the addition of new services without the need to add more hardware

Easier for operators to exploit revenue opportunities

Meet time-to-market challenges

Helps reduce CAPEX and OPEX needs

Ability to tailor the network "on demand" to customer needs

Automated traffic management

Improved bandwidth engineering

SDN and C-RAN are the helping hands that will help LTE realize its true potential

Summary

20

Confidentiality Statement

Confidentiality

•This material contains information that is confidential and proprietary to Aricent.

•Recipient may not distribute, copy, print or repeat information in the document

Legal Statement

•This presentation sets forth Aricent’s current thought and is subject to change at any time without notice. Aricent is not liable for any direct or intended commitments as may be inferred from the ensuing presentation.

•All information shared in this document is covered under a mutually signed Non-Disclosure Agreement.

21 Proprietary & Confidential. ©Aricent Group 2013