3G Mechanism Technology Analysis and Comparison

8/13/2019 3G Mechanism Technology Analysis and Comparison

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3G Mechanism Technology Analysis and Comparison





Table of ContentsTable of Contents

Training.huawei.com

Chapter 1 3G Mechanism Analysis

Chapter 2 WCDMA and CDMA2000

Chapter 3 Key factors for mechanism selection



Different Demands for Different PeriodsDifferent Demands for Different Periods

Early demands Current demands New demands

Speech quality Large capacity Larger capacity

Basic conversation

capabilities

Low-s

peed rate data Higher spectrum

utilization

Privacy High-speed dataaccess

High speech QoSHigher QoS

Safer service

Lower operation cost



Early service Current service New service

Higher-quality speech

UserSingle service High-quality speech High-speed mobile

access

Not high QoS Simple low-speeddata service

Positioning service

Bad privacy Short message Multimedia and e-commerce Personalized service

Lower operation cost

Operator High operationcost

Low operation cost Higher spectrumutilization

Low spectrum

utilization

High spectrum

utilization

Multiple services

Single service A few value-addedservices

QoS improvement

Improvement ofmarket com etition

Different Services for Different DemandsDifferent Services for Different Demands



Different Technologies for Different Services

AMPS

TACS

NMT

!

GSMGSM

CDMACDMA

IS95IS95

TDMATDMA

IS-136IS-136

PDCPDC

1st

generation in 1980s Analog

2nd

generation in 1990sDigital 3rd

generationI MT- 2000

UMTSUMTS

WCDMAWCDMA

cdmacdma

20002000

Driven bydemands

Driven bydemands

A n a

l o g t e c h n ol o g y

Di gi t a

l t e ch n ol o g y

S p e

e c h s er v i c e

B r o a d b

an d s er v i c e

TD-

SCDMA

TD-

SCDMA

3G provides perfect solutions to integrated services for users and operators.



3Gmechanism

WCDMAWCDMACore network: MAP and GPRS-based

network

Radio transmission technology:

WCDMA"FDD/TDD

TD-SCDMACore network: MAP-based

networkRadio transmission technology:

TD-SCDMA

cdma2000Core network: ANSI 41 and MIP

network

Radio transmission technology:

cdma2000

CDMA technology is the core of 3G.

Core of 3G- CDMA TechnologyCore of 3G- CDMA Technology



Cdma2000 Technology Mechanism-Network FeaturesCdma2000 Technology Mechanism-Network Features

2. PS domain: extended into the broadband packet

network based on IWF

4. Air interface: be compatible with IS95

1. CS domain: inherit 2G CDMA network, introducing

the service platform with WIN as the basic architecture

3. Radio access network: use ATM as its platform,

providing a variety of adaptation layer interfaces.



Features of cdma2000 RTT TechnologyFeatures of cdma2000 RTT Technology

BTS synchronization mode:

require GPS/GLONASS

Channel bandwidth:

N*1.25Mhz

Chip rate: N*1.2288

Mcps N=1,3,6,9,12 speech code:8K/13K

QCELP 8K EVRC

Transmit diversity mode:

OTD and STS

Modulation mode:

uplink QPSK

Downlink BPSK

Power control: uplink/downlink

closed loop power control,

and outer loop power control

Channel code:

Convolutional Code and

TURBO code

Demodulation mode:pilot-assistant coherence

demodulation

CDMACDMA

2000 2000



cdma2000 1X Technology Featurescdma2000 1X Technology Features

l IS-95A/B is the subset of cdma2000.l Support the chip rate of 1.2288 Mcps

l Support spread spectrum demodulation: forward QPSK andreverse HPSK

l Support reverse pilot and coherence demodulation

l Support fast forward and reverse power control

l Support forward transmit diversity, including OTD and STS

l Add Turbo code to channel code

l Support changeable frame length, such as 5ms, 10ms, 20ms,40ms and 80ms

l Support F-QPCH to prolong standby time of the MS

l Support the maximum rate of 307.2kbps

l Support QoS negotiation

l Support multimedia servicel Support 8K/13K QCELP 8 kbps EVRC

l Feature channel capacity which are two times of that in IS-95A/B



cdma2000 1X Candidate Enhancement Technologiescdma2000 1X Candidate Enhancement Technologies

l HDR put forward by Qualcomm, supporting data service with the

maximum rate of 2.4Mbps

l 1XTREME put forward by Motorola and Nokia Incorporations jointly

l LAS-CDMA put forward by China

l HDR-based 1X-EV-DO version has completed for 3GPP2. 1X-EV-DV

version is now being discussed based on technologies put forward by

Motorola, Lucent and LAS-CDMA .



cdma2000 3X Technology Featurescdma2000 3X Technology Features

0 1MHz 2 MHz 3 MHz 4 MHz 5 MHz

0 1MHz 2 MHz 3 MHz 4 MHz 5 MHz

1.25 MHz

Forward

Link

Reverse

Link

0 1MHz 2 MHz

0 1MHz 2 MHz

1.25 MHz

Forward

Link

Reverse

Link

Chip rate: 3*1.2288 McpsMax. access rate: 2Mbps



Cdma2000 TransitionCdma2000 Transition

1 IS-95A/B carrier cdma2000 1X carrier

cdma2000 is compatible with IS-95A/B. Add SCH to support packet services.

Add cdma2000 1X BSC and cdma2000 BTS to realize smooth transition,

namely, upgrading service smoothly requires adding devices.

1 IS-95A/B carrier

+ 2 cdma2000 1X carrier



WCDMA Development HistoryWCDMA Development History

GSMGSM

1998 1999 2000 2001 2002 2003 2004 2005

GSM + GPRSGSM + GPRS

WCDMAWCDMA

E v o l u

t i o n a n

d d e

v e l o p m

e n t E v o

l u t i o

n a n

d d e

v e l o p m

e n t



WCDMA Technology Mechanism-Network FeaturesWCDMA Technology Mechanism-Network Features

1. The core network is based on evolution of GSM/GPRS network andkeeps compatibility with GSM/GPRS network.

4. Based on ATM technology, UTRAN processes speech and packet servicesin a unified way and evolves into IP.

3. The core network is logically divided into CS domain and PS domain,

implementing CS services and PS services respectively.

2. The core network can be based on TDM, ATM and IP technologies and

evolve into the network with full-IP architecture.

5. MAP and GPRS tunnel technologies are the core of mobility management

mechanism in the WCDMA system.



Basic Contents of WCDMA

Modulation mode: uplink: QPSK; downlink:

QPSK

speech code: AMR

Channel code: convolutional codeand Turbo code

Demodulation mode: pilot-assistant coherence

demodulation

Transmit diversity mode: TSTD, STTD and FBTD

Power control: uplink/downlink closed loop power

control, and outer loop power control

BTS synchronization mode: support asynchronous and

synchronous BTS running

Signal bandwidth: 5MHz; chip rate: 3.84Mcps





TD-SCDMA Development HistoryTD-SCDMA Development History

Began to research

TD-SCDMA

Formed TD-SCDMA

resolution

As one of resolutions for

3GPP, TD-SCDMA was

approved in the 3GPP

conference.

1990

1998

1999

Integrated TD-SCDMA

and WCDMA-TDD

technologies

2000



TD-SCDMA Technology Mechanism-Network FeaturesTD-SCDMA Technology Mechanism-Network Features

1. The core network is based on evolution of GSM/GPRS networkand keeps compatibility with GSM/GPRS network.

4. Based on ATM technology, UTRAN processes speech and packetservices in a unified way and evolves into IP.

3. The core network is logically divided into CS domain and PS domain,

implementing CS services and PS services respectively.

2. The core network can be based on TDM, ATM and IP technologies

and evolve into the network with full-IP architecture.

5. MAP and GPRS tunnel technologies are the core of mobility management

mechanism in the WCDMA system.

TD-SCDMA technology mechanism will adopt core network structure of

WCDMA mechanism.



TD-SCDMA Technology FeaturesTD-SCDMA Technology Features

TD-SCDMA, put forward by CWTS, is the first Chinese communication

standard accepted by ITU.

Ø Smart Antenna

Ø Synchronous CDMA

Ø Software Radio

Ø Smart antenna+ joint detection

Ø Multi-slot CDMA+DS-CDMA

Ø Synchronous CDMA

ØChannel coding/decoding andinterleaving (the same as 3GPP)

ØRelay handoff

The main features of TD-SCDMA: 3S Key technologies of TD-SCDMA



Advantages of TD-SCDMA System

l Be able to use spectrum efficiently because no binate band class is required. In

addition, band class assignment is also simple. Whereas, the FDD technology in

the WCDMA system requires binate band class.

l Be more suitable for asymmetrical services because uplink and downlink

resources can be flexibly allocated, including Internet, multimedia application and

file transfer service. Whereas, the WCDMA system has to waste one uplink band

class up to now.

l Be easy to use such new technologies as smart antenna to improve performance

and reduce cost due to symmetrical electric wave propagation. The reason is

that uplinks and downlinks are of pertinence and work on the same frequency.

Whereas, the WCDMA system do not feature pertinence because its uplinks and

downlinks do not use the same frequency.

l

Feature low cost of TDD equipment due to corresponding channels. Therefore,receiver can be simplified. In addition, single-chip IC can be used to realize RF

transceiver due to no requirements for receiving and sending isolation.



Disadvantages of TD-SCDMA System

l Inter-BTS synchronization: Inter-BTS synchronization is required toreduce interference between BTSs.

l Interference in TDD: As a synchronization system, the TDD has high

requirements for synchronization which plays a very important role in the

communication system. In addition, that uplinks and downlinks are on

the same band class adds interference type.

l Narrower coverage compared with the WCDMA system

l Mobility speed: TDD required by ITU-R supports a maximum rate of

120km/h, while the FDD supports a maximum rate of 500km/h.

l Transmit power: TD-SCDMA results in pulse power interference due to

factors of TDMA, thereby requiring great transient transmit power. But

FDD has not such a problem because it is transmitted on all slots.



Comparison among Three Mechanisms

WCDMA

WCDMA cdma2000 TD-SCDMAStructure of

receiver RAKE RAKE RAKE

Closed power control Support Support Support

Cross-area handoff Soft/hard handoff Soft/hard handoff Relay handoff

Demodulation mode Coherence demodulationCoherence demodulationCoherence demodulation

Chip rate (Mcps) 3.84 N*1.2288 1.28

Transmit diversity

mode

TSTD

STTD

FBTD

OTD

STSNone

Synchronization mode Asynchronization Synchronization Synchronization

Core GSM MAP ANSI-41 GSM MAP



SummarySummary

l This chapter introduces and compares technical features of

three 3G mechanisms. Engineers can have a better

understanding of various 3G mechanisms by studying

these features.




Training.huawei.com



Chapter 3 Key Factors for Mechanism Selection





Analysis of Key Factors

WCDMA c dma2 000

Power control1500Hz fast power control for inner loop

n Feature better anti-fading performance andprovide better conversation quality

n Increase capacity and coverage range

800Hz fast power controlfor inner loop

SynchronizationAsynchronization or synchronization (optional)

nConvenient BTS networking,

independent of GPS

n MS consumes more 13% of

electricity in the asynchronization mode

Synchronization (GPS)

n Simplify handoff and search processes



Analysis of Key FactorsAnalysis of Key Factors

WCDMA cdma2 000

Handoff Support soft/softer/inter-frequency hard/inter-GSMs handoff

n Introduce compressed mode and no disconnectionoccurs during inter-frequency or

inter-system measurement.

n Reduce call drop rate of the system

Support soft/softer/inter-frequency hard/

inter-IS-95 handoff

n Must disconnect communication with the originalcarrier and then synchronize and measure on

the new carrier again.

n Feature unstable speech quality to result in frequent

call drop. So, require adding extra Pilot Beacon

to BTS.

Transmit

diversity Support open loop transmit diversity

(TSTD and STTD) and

closed loop transmit diversity

nFeature stronger capability of

adapting channel environment

n Supported by terminals

nClosed loop transmit diversity provides

higher diversity gain and increasesdownlink capacity and coverage capability of

the system in the case of low-speed moving.

Support open loop transmit diversity (OTD and STS)only

n Not supported by terminals now



WCDMA has equal speech capability as cdma20001x.

Capacity of speech service (unit: Erlang/MHz/cell)

WCDMA simulation and test data are obtained from Huawei!s outside plant testing in Oct. 2004,

while cdma2000 test data are obtained from Huawei!s outside plant testing in Alug. 2001.

WCDMA features different speech code rate from cdma2000.

Analysis of Speech CapabilityAnalysis of Speech Capability

WCDMA (12.2Kbps)

Preset conditions

Simulation Test

cdma2000 (8Kbps)

Indoor s19.6 18.5 17.4

Outdoor walking 3 kilo/h 16.4 15.7 16.2

Vehicle mounted 120 kilo/h 15 14.1 13.2



Capacity of data service (unit: Kbps/MHz/cell)

WCDMA features greater data service capacity than cdma2000

#$%&

WCDMA simulation and test data are obtained from Huawei!s outside plant testing in Oct. 2001,

while cdma2000 test data are obtained from Huawei!s outside plant testing in Aug. 2001.

Analysis of Data CapabilityAnalysis of Data Capability

WCDMA cdma2000

Preset conditions

384Kbps 144 Kbps 64 Kbps 153.6 Kbps

Indoors 451 394 351 270

Outdoor walking 3 kilo/h 451 386 343 210

Vehicle mounted 120 kilo/h 350 300 279 210

R di C A l i



Results of test on core band class sensitivity of Huaweis WCDMA and cdma2000 are as

follows:

Site: ordinary city zone in outside plant in Shanghai; time : 2001/12 ; vehicle speed: 60km/s: testconditions: dual polarization antenna, 17.15dbi of gain, 25 meters of mounted height

Results of the test on Huaweis WCDMA coverage performance are as follows:

WCDMA has equal radio coverage capability as cdma2000 on the

core band class.

Radio Coverage AnalysisRadio Coverage Analysis

WCDMA cdma2000

Protocol Test Protocol TestBTS receiver sensitivity

(dBm)

-121 -125 -119 -127.5

Service Coverage radius

Uplink/downlink 144Kbps data service 5 kilo

Uplink/downlink 384 Kbps data service 3 kilo

12.2Kbps speech service 10.5 kilo



Smart antenna is one of most important enhancement

technologies in 3G.

l Compared with dual antenna receiving diversity, four antenna multi-beam handoff

doubles the system capacity and increases coverage area by 50%.

l Each user can reduce cost by 27% by adopting smart antenna technology to

establish mobile networks.

WCDMA standard can better support smart antenna

technology.

Analysis of Supporting Smart AntennaAnalysis of Supporting Smart Antenna

Key technologies to support

smart antenna WCDMA cdma2000

Multi-beam handoff technology Realized in the whole coverage area Realized within local hot spot area

Self-sensing antenna array

technology Define dedicated pilots in

standard and can be easilyrealized.

Not define downlink dedicated

pilots and cannot be easilyrealized.



3GPP Rel99

3GPP Rel4

3GPP Rel5

Time point whenfunctions are frozen

2000/03 2001/03 2002/03

GSM/GPRS core network

WCDMA FDD

CS IP speech bearer

CS Call Server/ MGW

IP real-timemultimedia

HSPDA

WCDMA standard is clearly classified and precisely made.

Support HSDPA technology and cater to requirements for future high-speed radio data service

Cater to the development trend of IP technology, and introduce IP by stages to realize it in thewhole network and to perfect standards

Realize forward compatibility with 2001/06 and the following protocols

Development of WCDMA StandardDevelopment of WCDMA Standard



IS-95A Time point when

specifications are

completed

1995 1998 2000

QCELP speech

code

9.6kbps

115.2kbps

8 code channel

binding

307.2kbps

Speech capacitydoubled cdma2000

1xEV-DO/DV

2002

DO: high-speed data service

DV: high-speed data service +

speech service

IS-95B

cdma20001x

cdma2000-3x

??

Uncertain factors occur to development of cdma2000 standard.

Support 1x EV technology and cater to requirements for future high-speed radiodata service

Be disputable on the development of cdma2000 1x EV-DO/DV in the industry.

Lag behind in terms of core network standard and technology

Development of cdma2000 StandardDevelopment of cdma2000 Standard

Analysis of Future High-Speed Data ServiceAnalysis of Future High-Speed Data Service



Analysis of Future High Speed Data Service

Development

Analysis of Future High Speed Data Service

Development

WCDMA and cdma2000 high-speed data services are compared as

follows:

WCDMA cdma2000

HSDPA 1X EV-DO 1X EV-DV

Standardized time 2002/03 2001 ?

Requirements for

network construction Smooth upgradeSupport data through

separate carrier Smooth upgrade

Highest data rate 10M 2.4M 2.4M

Terminal complexity Complex Require two sets of RF

and cost muchComplex

I t f O A l iI t f O A l i



WCDMA specifications is precisely made and strictly organized.

l All WCDMA interfaces are open based on 3GPP specifications.

l The pilot network of DoCoMo in Japan proved feasible to open Iub interface.

The preciseness of cdma2000 standard are to be strengthened.

l It is difficult for operators to complete type selection of equipment if IS95

devices from different manufacturers cannot realize interworking.

l BTSs and BSCs from different manufacturers cannot realize interworking with

each other if Abis interface is not opened.

Interface Openness AnalysisInterface Openness Analysis

Signaling Net orking and Roaming Anal sisSignaling Networking and Roaming Analysis



MCC MSIN/MINMNCIMSI (International Mobile Subscriber

Identity)

National Mobile Subscriber Identity

WCDMA and cdma2000 signaling networking and roaming are compared

as follows:

Signaling Networking and Roaming AnalysisSignaling Networking and Roaming Analysis

WCDMA cdma2000

Signaling network ITU 7 signaling network

Support global roaming

ANSI 7 signaling network in North America

Require establishing Gateway to resolve interworking

Mobile subscriber

identityIMSI

n The only to identify a mobile

subscriber globally

n Support global roaming

MIN

n Refer to the last 10 digits of IMSI,

excluding country number and mobile

network number

nMost part of MINs are allocated to North

America and only a few numbers (IRM)

are allocated internationally.

nCannot support international roaming

efficiently



SummarySummary



SummarySummary

l This chapter compares and analyzes WCDMA and

CDMA2000 from such aspects as key technologies,

service capability and protocol development. Engineers will

under their advantages and disadvantages by comparison.





Training.huawei.com



Chapter 3 Key Factors for Mechanism Selectio

Communication Market and ServiceCommunication Market and Service



GSM subscribers are about 660 million globally, accounting for 68% of

mobile subscribers all over the world.

CDMA subscribers are 100 million globally, accounting for 10% of mobilesubscribers all over the world. They are centered in North America and East

Asia.

Key factors for GSM to obtain a great success in 2G mobile market are asfollows:

" Precise and open standard, as well as global roaming

" Supported by many manufacturers

Note: Data is from 3GSM conference, released in Feb. 2002.

Development TrendDevelopment Trend

66000

10000

20000

010000

20000

30000

40000

50000

60000

70000

GSM CDMA Others

GSM CDMA Others

200 million

880 million

100 million

GSM CDMA Others

GSM

cdma

Others

Frequency Resources in ChinaFrequency Resources in China



1850 1900 1950 2000 2050 2100 2150 2200

ITU

1880 MHz

1980 MHz

1885 MHz

2025 MHz

2010 MHz

IMT 2000 IMT 2000

2110 MHz 2170 MHz

MSS MSS

PCSTDD

WLLFDDWLL

1 9 8 0

2025MHz

GSM1800

PCSFDDWLL

1 9 6 0

1 9 2 0

1 9 4 5

cellular (1)cellular (2) cellular (2)

1805 MHz

1 8 6 5

Frequency classification in IMT2000 and Europe is the same as that in China.

Frequency classification in North America conflicts with the core band class inChina.

Frequency Resources in ChinaFrequency Resources in China

Frequency resources Available mechanism

3G core band class

1920 1980/2110 2170MHz

60M in uplink/downlink respectively WCDMA (supported widely)Cdma2000 (lack support and require

changing frequency)

1880-1920 MHz

2000-2015 MHz2300-2400 MHz

TDD frequency

Total 155 MHz

TD-SCDMA

1800MHz band class 55MHz left GSM 1800

Maturity of 3G TechnologyMaturity of 3G Technology



WCDMA: The technology has been mature and its products are stepping into

commercial use stage.

Japanese NTT DoCoMo has been for commercial use.

Commercial system equipment and terminal products began to be available on the market

gradually since the next half year of 2002.

WCDMA terminals are as complex as cdma2000 terminals. The cost mainly depends on

market support.

cdma2000 system with 800M band class

Korean SKT has been for commercial use.

cdma2000 with 800MHz band class wins wide support from equipment and terminal

manufactures.

cdma2000 system with 3G core band class

There are few operators to select the mechanism with such a band class globally.

Band class translation results in changes to system designs, including equipment and

terminals.

Compatible instruments and terminals manufacturers make a slow progress, thereby

affecting R&D process of equipment manufacturers.

Maturity of 3G TechnologyMaturity of 3G Technology

3G Mechanism Selection for Various Operators (Top20)3G Mechanism Selection for Various Operators (Top20)



Adopting the unified band class globally, WCDMA features stronger roaming and global

service expansion capability.

Globally, only two operators announce to select cdma2000 with core band class but not

for commercial use up to now.

China Mobile (China) Own GSM networks

NTT DoCoMo (Japan) WCDMA

Verizon (USA) cdma2000

Italia Mobile (Italy) WCDMACingular (USA) WCDMA

D2 Vodafone (Germany) WCDMA

T-Mobil ( Germany) WCDMA

China Unicom (China) Own CDMA and GSM networks

AT&T (USA) WCDMA

Omnitel Vodafone (Italy) WCDMA

KDDI (Japan) cdma2000

France Telecom Mobiles (France) WCDMA

Telef "nica Moviles (Spain) WCDMAVodafone (Britain) WCDMA

SK Telecom (Korea) WCDMA/cdma2000

Am%rica M"vil (Mexico) Uncertain

BT Cellnet (Britain) WCDMA

SFR (France) WCDMA

Sprint (USA) cdma2000

Orange (Britain) WCDMA

3G Mechanism Selection for Various Operators (Top20)3G Mechanism Selection for Various Operators (Top20)

Industry Support StatisticsIndustry Support Statistics



Industry Support StatisticsIndustry Support Statistics

WCDMA cdma2000

System equipmentSupported by many manufacturers

Unavailable in large scale at in 2002

800M: supported by many manufacturers

3G core band class: lack support

Terminal productSupported by many manufacturers

Unavailable in large scale in 2002

800M: supported by many manufacturers

3G core band class: lack support

Chip Supported by many manufacturers Single

RF parts Have mature and stable suppliers800M: have been mature

3G core band class: difficult to obtain support from

MS, RF parts and module suppliers

Test instruments Supported by various instruments 800M: have been mature

3G core band class: noneG

Service chain WCDMA and iMode realized organiccombination

Still be at initial stage and have nosuccessful example

Network Construction Cost ForecastNetwork Construction Cost Forecast



Since GSM1800, cdma2000 and WCDMA isSince GSM1800, cdma2000 and WCDMA is

equipped with equal coverage capability,equipped with equal coverage capability, networknetwork

construction cost mainly depends on equipment costconstruction cost mainly depends on equipment cost..

Equipment cost mainly depends on industry chainEquipment cost mainly depends on industry chain

TechnologyTechnology

StandardizationStandardization

OutputOutput

Wide support or notWide support or not

Market competitionMarket competition

Network Construction Cost ForecastNetwork Construction Cost Forecast

Development of WCDMA TerminalsDevelopment of WCDMA Terminals



Japan has developed WCDMA commercial terminals based on3GPP 2001/06 protocol version in the next half of 2002.

Price of a MS is determined by the size of batch rather than

the absolute time.

Development of WCDMA TerminalsDevelopment of WCDMA Terminals

WCDMA Terminal Price and Performance

Forecast

WCDMA Terminal Price and Performance

Forecast



Price forecast of low-end MSs applicable to markets in China

( Price upon delivery)

Standby time and talk time

Tim e S tandby Talk Tim e

2001 55H 90M2002 150H 100M

2003 300H 110M

Main performance specificationsof a low-end MS are as follows:

Speech Packet Communication

E-mail

Large screen LCD(Monochrome type)

16 harmonies Ringer

Straight type

ForecastForecast

113

267

200

150

0

50

100

150

200

250

300

10 100 1000 10000

Quantity of terminals

'unit: ten thousand pieces(

Price'$(

SummarySummary



yy

l This chapter discusses some main factors for mechanism

selection. Engineers can know how to select a suitable 3G

mechanism by studying these factors.

ConclusionConclusion



l Apart from analyzing and comparing various 3G

mechanisms, this slide also introduces some factors to

be considered during mechanism selection.



Thank

you!

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3G Mechanism Technology Analysis and Comparison