Chapter 1 Wcdma System Overview

Basic Principles of WCDMA System WCDMA System Overview

Chapter 1 WCDMA System Overview

1.1 Development of Mobile Communications

Up till now the modern mobile communication has experienced two

generations and evolved into the third generation that is ongoing with

pre-commercialization. Many manufacturers have already carried out

their commercial trials in Europe and Asia.

The first generation is the analog cellular mobile communication

network in the time period from the middle of 1970s to the middle of

1980s. The most important breakthrough in this period is the concept

of cellular networks put forward by the Bell Labs in the 1970s, as

compared to the former mobile communication systems. The cellular

network system is based on cells to implement frequency reuse and

thus greatly enhances the system capacity.

The typical examples of the first generation mobile communication

systems are the AMPS system and the later enhanced TACS of USA,

the NMT and the NTT. The AMPS (Advanced Mobile Phone System)

uses the 800 MHz band of the analog cellular transmission system

and it is widely applied in North America, South America and some

Circum-Pacific countries. The TACS (Total Access Communication

System) uses the 900 MHz band and includes two versions: ETACS

(Enhanced TACS) in Europe and NTACS (Narrowband TACS) in

Japan. It is widely applied in Britain, Japan and some Asian countries.

2004-08-192004-10-26 Confidential Information of Huawei. No Spreading without Permission

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The main feature of the first generation mobile communication

systems is that they use the frequency reuse technology, adopt analog

modulation for voice signals and provide an analog subscriber channel

every other 30 kHz/25 kHz. However, their defects are also obvious:

1) Low utilization of the frequency spectrum

2) Limited types of services

3) No high-speed data services

4) Poor confidentiality and high vulnerability to interception

and number embezzlement

5) High equipment cost

6) Large volume and big weight

To solve these fundamental technical defects of the analog systems,

the digital mobile communication technologies emerged and the

second generation mobile communication systems represented by

GSM and IS-95 came into being in the middle of 1980s. The typical

examples of the second generation cellular mobile communication

systems are the DAMPS of USA, the IS-95 and the European GSM

system.

The GSM (Global System for Mobile Communications) is originated

from Europe. Designed as the TDMA standard for mobile digital

cellular communications, it supports the 64 kbps data rate and can

interconnect with the ISDN. It uses the 900 MHz band while the

DCS1800 system uses the 1800 MHz band. The GSM system uses

the FDD and TDMA modes and each carrier supports eight channels

with the signal bandwidth of 200 kHz.


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The DAMPS (Digital Advanced Mobile Phone System) is also called

the IS-54 (North America Digital Cellular System). Using the 800 MHz

bandwidth, it is the earlier of the two North America digital cellular

standards and specifies the use of the TDMA mode.

The IS-95 standard is another digital cellular standard of North

America. Using the 800 MHz or 1900 MHz band, it specifies the use of

the CDMA mode and has already become the first choice among the

technologies of American PCS (Personal Communication System)

networks.

Since the 2G mobile communication systems focus on the

transmission of voice and low-speed data services, the 2.5G mobile

communication systems emerged in 1996 to address the medium-rate

data transmission needs. These systems include GPRS and IS-95B.

The CDMA system has a very large capacity that is equivalent to ten

or even twenty times that of the analog systems. It also has good

compatibility with the analog systems. Currently some countries and

regions such as USA, Korea and Hong Kong have put the CDMA

system into operation to provide services for subscribers. As the

narrowband CDMA technologies come into maturity at a time later

than the GSM technologies, their application far lags behind the GSM

ones and currently they have only found large-scale commercial

applications in North America, Korea and China. The major services of

mobile communications are currently still voice services and low-

speed data services. With the development of networks, data and

multimedia communications have also witnessed rapid development;


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therefore, the target of the 3G mobile communication is to implement

broadband multimedia communication.

The 3G mobile communication systems are a kind of communication

system that can provide multiple kinds of high quality multimedia

services and implement global seamless coverage and global

roaming. They are compatible with the fixed networks and can

implement any kind of communication at any time and any place with

portable terminals.

Put forward in 1985 by the ITU (International Telecommunication

Union), the 3G mobile communication system was called the FPLMTS

(Future Public Land Mobile Telecommunication System) and was later

renamed as IMT-2000 (International Mobile Telecommunication-2000).

The major systems include WCDMA, cdma2000 and UWC-136. On

November 5, 1999, the 18th conference of ITU-R TG8/1 passed the

Recommended Specification of Radio Interfaces of IMT-2000 and the

TD-SCDMA technologies put forward by China were incorporated into

the IMT-2000 CDMA TDD part of the technical specification. This

showed that the work of the TG8/1 in formulating the technical

specifications of radio interfaces in 3G mobile communication systems

had basically come into an end and the development and application

of the 3G mobile communication systems would enter a new and

essential phase.


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1.1.1 Standardization Organizations

The standardization of 3G mobile communication systems are in fact

pushed forward and implemented by two standardization

organizations: 3GPP (3rd Generation Partner Project) and 3GPP2.

Established in December 1998, the 3GPP is composed of the

European ETSI, the Japanese ARIB, the Korean TTA and the

American T1. It adopts the WCDMA technologies of Europe and

Japan to construct a new radio access network and smoothly evolves

a core switching network from the existing GSM mobile switching

network to provide more diversified services. The UTRA (Universal

Terrestrial Radio Access) is used as the radio interface standard.

In January 1999, the 3GPP2 composed of the American TIA, the

Japanese ARIB and the Korean TTA also formally came into being.

The cdma2000 and UWC-136 technologies are applied for radio

access and the cdma2000 technologies adopt the Qualcomm patents

to a large extent. ANSI/IS-41 is used for the core network.

One formal member of the above two standardization organizations is

the China Wireless Telecommunications Standard Group (CWTS) and

two Chinese companies (Huawei and Datang) are two independent

members of the 3GPP organization.

1.1.2 3G Evolution Policies

In general, the evolution policies formulated by 3GPP and 3GPP2 are

progressive. This has the following benefits:


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Guaranteeing the existing investment and operators’

benefits

Facilitating the smooth transition of the existing

technologies

From the perspective of development, the process of evolution from

the existing 2G mobile communication systems to the IMT-2000 is a

vital issue. It relates to the reuse of the existing networks (the

construction of new networks should not be the optimal solution) and

the development of multiple 2G digital network systems towards the

same standard.

1. Policies of evolution from GSM to WCDMA

The policies of evolution from GSM to WCDMA should be as follows:

The present GSM → HSCSD (High Speed Circuit Switched Data at

the rates from 14.4 kbps to 64 kbps) → GPRS (General Packet Radio

Service at the rate of 144 kbps) → Smooth seamless evolution from

the network service coverage ultimately to IMT-2000 WCDMA (DS).

1) HSCSD: High Speed Circuit Switched Data

HSCSD is a feature to allocate multiple full-rate voice channels to the

HSCSD structure. Its purpose is to provide the mixture of multiple

services at different air interface subscriber rates with the single

physical layer structure. Its benefits lie in the higher data rates (up to

64 kbps; the maximum data rate depends on the manufacturers) and

the use of the existing GSM data technologies by slightly modifying

the GSM system.

2) GPRS: General Packet Radio Service


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The major benefits of GPRS are as follows:

Standard radio packet switching Internet/Intranet access

applicable to all the places of GSM coverage

Variable peak data rate that ranges from several bits per

second to 171.2 kbps (the maximum data rate depends on the

manufacturers)

Charging by the actual data volume: This charging

method enables the subscribers to pay the cost of the actual data

volume transmitted while remaining online all the days

Support for the existing services and new application

services

Packetization over the radio interfaces to optimize the

sharing of radio resources

Packet switching technology to optimize the sharing of

network resources

Capability of extension to the future radio protocols

Based on the existing GSM part, the packet switching GPRS network

architecture has the new network function part:

3) WCDMA: Wideband Code Division Multi Access

The WCDMA has become a new mature technology aiming at the

UMTS/IMT-2000. It can satisfy all the requirements listed by the ITU to

provide very effective high-speed data services and high quality voice

and image services. In the process of evolution from GSM to

WCDMA, only the core network part is smoothly evolved. As the

change of the air interface is revolutionary, so is the evolution of the

radio access network part.


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2. Policies of evolution from IS-95 to cdma2000

After the IS-95A (at the rates of 9.6/14.4 kbps) is evolved to the IS-

95B (at the rate of 115.2 kbps) and ultimately to cdma2000 1X, the

system can provide higher capacity and a higher data rate (144kbps)

and can support the burst mode as well as adding new supplemental

channels. The cdma2000 1X EV with enhanced technologies can

provide higher performances.

The IS-95B is different from the IS-95A in that multiple channels can

be bound in the IS-95B system. These two are basically the same in

essence can they can coexist in the same carrier. In contrast, the

cdma2000 1X has greater improvements and its system equipment

can support 1X terminals and IS-95A/B terminals simultaneously.

Therefore, these three systems (IS-95A/IS-95B/1X) can coexist in the

same carrier. For the cdma2000 system, the gradual replacement

method can be applied in the transition from 2G systems to 3G

systems. In other words, one carrier of the 2G systems can be

compressed to become a 3G carrier to provide the services of medium

and higher rates to the subscribers. As the 3G systems have more

and more subscribers, the number of carriers used in the 2G systems

can be gradually reduced while more carriers can be added to the 3G

systems. Through this kind of smooth upgrading, the network

operators can not only provide various latest serves to the subscribers

but also well protect the investment of the existing equipment.

In the process of evolution to the 3G systems, the evolution of such

wireless equipment as BTS and BSC deserves special attention. The

protection of operators’ investment has been fully taken into account


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in the formulation of the cdma2000 standard and many radio indices

of the 3G systems are the same as in the 2G systems. From the point

of view of the BTS, the radio parts such as antenna, RF filters and

power amplifiers are all reusable while the baseband signal

processing part needs to be replaced.

There are currently two branches in the evolution to the cdma2000 1X

EV: 1) The cdma2000 1X EV-DO that only supports data services; and

2) the cdma2000 1X EV-DV that supports both data services and

voice services. For the cdma2000 1X EV-DO that only supports data

services, the HDR put forward by Qualcomm has been determined;

while for the cdma2000 1X EV-DV that supports both data services

and voice services, there are several proposals at present (one of

them is the LAS-CDMA technology submitted by China) and these are

presently in the process of review.

3. Policies of evolution from DAMPS to UWC-136

The first step of evolution from IS-136 (DAMPS) to UWC-136 is to

implement the GPRS-136 and the second step is to implement UWC-

136 (Universal Wireless Communications). The EDGE-based

technologies have been decided for UWCC and TIA TR-45.3, this

means that the GPRS network architecture will be used to support the

136+ high-speed data transmission. The GPRS-136 is the official

name of the 136+ packet switched data service and its high-layer

protocols (L3 protocols and above) are fully the same as those of the

GPRS system, considering the economical aspect of the

implementation. It provides the same capacity as the GPRS of GSM

and its subscribers can have access to two forms of data networks: IP 2004-08-192004-10-26 Confidential Information of Huawei.

No Spreading without PermissionPage9, Total24


and X.25. Its major purpose is to reduce the technical difference

between TIA/EIA-136 and GSM GPRS so that the subscribers can

roam between GPRS-136 and GSM GPRS networks. One of the

policies for the American TIA to develop the 3G systems is to

implement convergence of the 3G systems with the GSM system that

also uses the TDMA access mode. This is quite beneficial for the

economics of global roaming and products and it also implements the

coordination protocol between UWCC and ETSI. What’s more

important, it enables the TDMA to player a more important role in the

3G systems.

1.2 Types and Differences of 3G Systems

1.2.1 Origin of the Multiple Systems

Currently the 3G research work of ITU is mainly undertaken by 3GPP

and 3GPP2. The goal of ITU in terms of 3G is to establish the ITM-

2000 family and implement global roaming between different 3G

systems.

Family concept

1) Network part

In one intermediate meeting of ITU-T SG11 in March 1997, the ITM-

2000 Family Concept put forward in Europe was passed. This concept

was based on the existing networks and involved at least two major

standards: GSM MAP and IS-41.

2) Radio interface part


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In the ITU-R TG8/1 meeting in September 1997, the discussion on the

radio interface family concept started. In a special meeting of TG8/1 in

January 1998, the concept of suite was put forward and applied and

this put the family concept out of use. This means that there may be

more than one radio interface standard but the concept of more than

one standard is not yet accepted, rather, these different standards are

expected to ultimately form a unified standard.

The following two factors have caused various technical differences:

1) Relationship with 2G

The network part must be compatible with 2G, that is, the 3G networks

are gradually evolved from the 2G networks. There are two major 2G

core networks: GSM MAP and IS-41.

Radio interfaces: The American IS-95 CDMA and IS-136 TDMA

operators emphasize on the backward compatibility (evolutional) while

the European GSM and Japanese PDC operators emphasize on the

backward incompatibility of the radio interface (revolutionary).

The correspondence between the core networks and the radio

interfaces is shown in Figure 1-1 below:


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Figure 1-1 Correspondence between the core network and the radio access network

interface

3) The important role of frequency spectrum on technical

selection

In terms of frequency spectrum, the key issue is that the ITM-2000

frequencies allocated by ITU have already been applied to the PCS

service in USA. Because the USA requires the sharing of frequency

spectrum with 2G systems, the backward compatibility of the radio

interfaces is especially emphasized and technically the USA requires

gradual evolution. In contrast, most of the other countries have new

IMT-2000 frequency bands that feature very large flexibility. What’s

more, the intellectual property rights play a very significant role, for

example, Qualcomm has its own patent declaration. Competition is

also a major factor to contribute to the technical differences.


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1.2.2 RTT Technical Proposal

The eighth research group of ITU-R, i.e. the TG8/1 Task Group is

responsible for promoting the assessment and merge of IMT-2000

Radio Transmission Technology (RTT). Up till September 1998, there

have been up to 16 RTT proposals including the MSS (Mobile Satellite

Service). They all come from 16 RTT assessment groups of IMT-2000

and are listed as follows:

1) UTRA WCDMA (Europe)

2) DECT (Europe)

3) cdma2000 (USA)

4) UWC-136 (USA)

5) WIMS WCDMA (USA)

6) WCDMA/NA (USA)

7) WCDMA (Japan)

8) TD-SCDMA (China)

9) Global CDMA (Synchronous, Korea)

10) Global CDMA (Asynchronous, Korea)

11) LEO satellite system SAT-CDMA

12) ESA wideband satellite system SW-CDMA

13) CDMA/TDMA hybrid bandwidth satellite system SW-

CTDMA

14) ICO RTT

15) INMARSAT satellite system Horizons

16) Iridium LLC satellite system INX


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Among these proposals, the first ten are RTT proposals for the IMT-

2000 terrestrial system and the last six reflect the efforts of

incorporating the MSS (Mobile Satellite Service) into the IMT-2000.

These proposals reflect the concern of many countries as to the future

mode of IMT-2000 and their basic wishes to exercise effective

influence. However, as viewed from the market basis, backward

compatibility and overall features, the UTRA WCDMA of ETSI and the

cdma2000 of USA are the most competitive; therefore, the key to the

merge of RTT lies in the progress of effectively merging these two

proposals.

1.2.3 Technical Merge

IMT-2000 includes both the Terrestrial Mobile Service (TMS) and the

Mobile Satellite Service (MSS). The suggestion of one globally

uniform and better-merged 3G mobile communication standard is

conducive to whether operators, manufacturers, subscribers and

policy planning & management bodies, so it is warmly welcomed by all

countries in the world.

As far the sixteen RTT candidate schemes are concerned, the

ultimate result of merging terrestrial mobile communications will bring

the biggest competitiveness to the WCDMA (DS) of ETSI and the

cdma2000 of USA TIA in terms of the FDD mode; while for the TDD

mode, the TD-CDMA put forward by ETSI UTRA and the D-SCDMA

put forward by China CATT will be the major objects of further

integration. At the end of March 1999, Ericsson and Qualcomm

reached a series of agreements on the IPR and this act cleared way


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the obstacles from intellectual property rights for promoting a global

CDMA standard. At the end of May 1999, the Operator Harmonization

Group (OHG) composed of 31 global major operators and 11 major

manufacturers put forward a merge proposal of the IMT-2000. This

proposal played a positive role in promoting the unification of the

major parameters (chip rate, pilot structure, core network protocol

based on GSM-MAP and ANSI-41). All the participants unanimously

agreed that the chip rate should be 3.84Mcps for FDD-DS-CDMA and

3.6864Mcps for FDD-MC-CDMA, which is also called FDD-cdma2000-

(MC). In June 1999, the 17th meeting of TG8/1 was held in Beijing. In

this meeting, a framework agreement was reached on

Recommendations Rec, IMT and RSPC of the technical specifications

of radio interfaces. 3GPP, 3GPP2 and the Standards Development

Organizations (SDOs) were encouraged to support the above OHG

proposal and TG8/1 Task Group was appointed to carry out more

detailed work of the MSS proposal.

The 18th meeting of ITU TG8/1 was held in Helsinki, Finland in

November 1999, and the Recommended Specification of Radio

Interfaces of IMT-2000 was adopted. This meant that the TG8/1's work

in formulating the technical specifications of radio interfaces in the 3G

mobile communication systems had basically come to an end and the

development and application of 3G mobile communication systems

would enter the essential phase. TD-SCDMA, WCDMA and cdma2000

were determined as the ultimate three technical systems.


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1.2.4 Comparison Among the Three Major Technical Systems

1. WCDMA

Formulated by the European standardization organization 3GPP,

WCDMA is widely supported by the global standardization

organizations, equipment manufacturers, component suppliers and

operators. It will become one of the mainstream future 3G systems.

The core network evolves on the basis of and can thus be compatible

with the existing GSM/GPRS networks.

It can be based on the TDM, ATM and IP technologies to evolve

towards the all-IP network architecture.

Logically, the core network comprises two parts: The circuit domain

and the packet domain to complete the circuit-switched services and

the packet-switched services respectively.

Based on the ATM technology, the UTRAN uniformly processes voice

and packet services and evolves towards the IP network architecture.

MAP and GPRS tunneling technologies are the core of the mobility

management mechanism in the WCDMA system.

The air interface adopts the WCDMA technologies with the signal

bandwidth of 5 MHz and the chip rate of 3.84 Mcps. It uses the AMR

voice encoding scheme and supports the synchronous/asynchronous

Node B operation mode. Besides, the following modes are applied in

the WCDMA system: Uplink/downlink closed loop power control plus

outer loop power control; open loop (STTD & TSTD) and closed loop

(FBTD) transmit diversity; pilot-assisted coherent demodulation; 2004-08-192004-10-26 Confidential Information of Huawei.



convolutional coding and Turbo coding; QPSK modulation in both the

uplink and the downlink.

2. cdma2000 system

The cdma2000 system is a 3G standard put forward on the basis of

the IS-95 standard. Its standardization work is currently undertaken by

3GPP2.

Circuit Switched (CS) domain: Adapted from the 2G IS95 CDMA

network, the circuit domain has introduced a service platform based

on the WIN infrastructure.

Packet Switched (PS) domain: A packet network based on the Mobile

IP technology.

Radio Access Network (RAN): Based on the ATM switch platform, it

provides abundant adaptation layer interfaces.

The air interface adopts the cdma2000 technologies and is compatible

with the IS95. The signal bandwidth is N1.25MHz (N = 1, 3, 6, 9, 12)

and the chip rate is N1.2288Mcps. It uses the 8K/13K QCELP or 8K

EVRC voice coding mode and its BTS needs to run in the

GPS/GLONESS synchronous mode. The following modes are applied

in the cdma2000 system: Uplink/downlink closed loop power control

plus outer loop power control; OTD and STS transmit diversion in the

forward direction to improve the anti-fading capacity of channels and

the signal quality of the forward channels; pilot-assisted coherent

modulation in the reverse direction to improve the demodulation

performance; convolutional coding and Turbo coding; BPSK in the

uplink and QPSK in the downlink. 2004-08-192004-10-26 Confidential Information of Huawei.



3. TD-SCDMA system

The TD-SCDMA standard is put forward by the Chinese Wireless

Telecommunication Standard (CWTS) Group and now it has been

merged into the specifications related to the WCDMA-TDD of 3GPP.

The core network evolves on the basis of and can thus be compatible

with the existing GSM/GPRS networks.

It can be based on the TDM, ATM and IP technologies to evolve

towards the all-IP network architecture.

Logically, the core network comprises two parts: The circuit domain

and the packet domain to complete the circuit-switched services and

the packet-switched services respectively.

Based on the ATM technology, the UTRAN uniformly processes voice

and packet services and evolves towards the IP network architecture.

MAP and GPRS tunneling technologies are the core of the mobility

management mechanism in the WCDMA system.

The air interface adopts the TD-SCDMA mode.

The TD-SCDMA features 3S: Smart antenna, Synchronous CDMA

and Software radio.

The key technologies used in TD-SCDMA include Intelligent Antenna

+ Joint Detection, Multi-slot CDMA + DS-CDMA, Synchronous CDMA,

Channel Coding/Decoding and Interleaving (the same as in 3GPP)

and Baton Handover.

A comparison of the above three systems is given in the table below.


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Table 1-1 Comparison among the three major technical systems

System WCDMA cdma2000 TD-SCDMA

Using countries Europe and Japan USA and Korea China

Inheritance

fromGSM Narrowband CDMA GSM

Synchronous

mode

Asynchronous/

synchronousSynchronous

Synchronou

s

Chip rate 3.84Mcps N×1.2288Mcps 1.28Mcps

Signal

bandwidth5MHz N×1.25MHz 1.6MHz

Air interface WCDMAcdma2000 compatible

with IS-95TD-SCDMA

Core network GSM MAP ANSI-41 GSM MAP

1.3 3G Frequency Spectrum

ITU has allocated 230 MHz frequency for the 3G mobile

communication system IMT-2000: 1885 MHz ~ 2025MHz in the uplink

and 2110v~ 2200 MHz in the downlink. Of them, the frequency range

of 1980 MHz ~ 2010 MHz (uplink) and that of 2170 MHz ~ 2200 MHz

(downlink) are used for mobile satellite services. As the uplink and the

downlink bands are asymmetrical, the use of dual-frequency FDD

mode or the single-frequency TDD mode may be considered. This

plan was passed in WRC92 and new additional bands were approved

on the basis of the WRC-92 in the WRC2000 conference in the year

2000: 806 MHz ~ 960 MHz, 1710 MHz ~ 1885 MHz and 2500 MHz ~

2690 MHz, as shown in Figure 1-2 below.


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D O C U M E N T T Y P E

T y p e U n i t O r D e p a r t m e n t H e r eT y p e Y o u r N a m e H e r e T y p e D a t e H e r e

1 8 5 0 1 9 0 0 1 9 5 0 2 0 0 0 2 0 5 0 2 1 0 0 2 1 5 0 2 2 0 0 2 2 5 0

R e s e r v e

I M T 2 0 0 0G S M 1 8 0 0 D E C T M S S

M S SI M T 2 0 0 0P H S M S SI M T 2 0 0 0

I M T 2 0 0 0

M S SI M T 2 0 0 0I M T 2 0 0 0

I M T 2 0 0 0

M S SI M T 2 0 0 0

M S S

A D B E F A B C M S S

M S S M S S

G S M 1 8 0 0 , P C S

D FEB BC

I T U i d e n t i f i c a t i o n s

E u r o p e

C h i n a

J a p a n ,K o r e a ( w / o P H S )

N o r t h A m e r i c a

1 7 0 0 1 7 5 0 1 8 0 09 5 0 1 0 0 08 0 0 8 5 0 9 0 0

I M T 2 0 0 0I M T 2 0 0 0

G S M

C e l l u l a r

P D C

C e l l u l a r

P C SM S S

G S M

P r e v i o u s I M T - 2 0 0 0 t e r r e s t r i a l b a n d s

N e w I M T - 2 0 0 0 t e r r e s t r i a l b a n d s

Figure 1-2 Frequency spectrum allocation of WRC-2000

The European Union (EU) also attached great importance to 3G

mobile communication systems and the European

Telecommunications Standards Institute (ETSI) started the research

work of 3G mobile communication standardization as early as over ten

years ago and it established a UMTS (Universal Mobile

Telecommunication System) Forum that was composed of operators,

equipment manufacturers and telecommunication management

organizations. In 1995, the technical proposal for frequency spectrum

division was submitted formally to the ITU.

In Europe, the allocation of frequency spectrum is as follows: 1900

MHz ~ 1980MHz, 2010 MHz ~ 2025MHz and 2110 MHz ~ 2170MHz,

totaling 155 MHz.

The situation in North America is rather complex, as shown in Figure

1-2. The 1850 MHz ~ 1990 MHz band among the 3G low bands has

already allocated for PCS use and it has been divided into two 15

MHz and two 5 MHz bands. Since the PCS service has already


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occupied the frequency spectrum of IMT-2000, the uplink band of the

adjusted IMT-2000 even needs to be shared together with the

downlink band of PCS. This kind of arrange is not suitable for the

high-transmit and low-receive configurations of ordinary base stations.

In Japan, the frequency band of 1893.5 MHz ~ 1919.6 MHz has

already been allocated for PHS use and the 3G bands totaling 135

MHz (2 × 60 MHz + 15 MHz) are still available: 1920 MHz ~

1980MHz, 2110 MHz ~ 2170 MHz, 2010 MHz ~ 2025 MHz). At

present, Japan is endeavoring to clear the conflicts with the

frequencies for 3G mobile communications.

Korea has the same allocated frequency as in ITU Recommendations,

i.e., 170 MHz.

The WCDMA FDD mode uses the following frequency spectrum

(bands other than those specified by 3GPP may also be used): Uplink

1920 MHz ~ 1980 MHz and downlink 2110 MHz ~ 2170 MHz. Each

carrier frequency has the 5M band and the duplex spacing is 190

MHz. In America, the used frequency spectrum is 1850 MHz ~ 1910

MHz in the uplink and 1930 MHz ~ 1990 MHz in the downlink and the

duplex spacing is 80 MHz.

The frequency spectrum used by the WCDMA TDD mode (including

the high bit rates and the low bit rates) is as follows (bands other than

those specified by 3GPP may also be used):

1) Uplink 1900 ~ 1920MHz and 2010 ~ 2025MHz

2) America: Uplink 1850 MHz ~ 1910 MHz and downlink 1930 MHz ~

1990 MHz.


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3) America: 1910 MHz ~ 1930 MHz in both the uplink and the

downlink

In special cases (such as the boundary area of two countries), the

TDD mode and the FDD mode may coexist in the same frequency

band and 3GPP TSG RAN WG4 is currently researching this situation.

There is only the FDD mode in the cdma2000 system and currently

there are a total of seven band classes, of which Band Class 6 is the

1920 MHz ~1980 MHz/2110 MHz ~ 2180 MHz band stipulated in IMT-

2000.

In China, according to the present radio frequency division, mobile

services, fixed services and spatial services are using the 1700 MHz ~

2300 MHz band, which is currently serving plenty of microwave

communication systems and a certain number of wireless location

devices. In December 1996, the State Radio Regulatory Committee of

P. R. China re-planned and adjusted some terrestrial radio service

frequencies of 2 GHz to adapt to the needs of cellular mobile

communication development and radio access. However, the

frequency spectrum still conflicts with the 3G mobile communication

systems, that is, the 1.9 MHz band for public cellular mobile

communications and the radio access band have both taken up some

of the IMT-2000 bands.

Therefore, the 3G mobile communication systems have to share the

limited frequency resources with the existing radio communication

systems. With the development of technologies and services, the

planning and adjustment of IMT-2000 bands must be well done to

stimulate the operators, scientific research organizations/institutions, 2004-08-192004-10-26 Confidential Information of Huawei.



manufacturers and other bodies to actively develop the 3G mobile

communication systems, so as to meet both the short-term and the

long-term frequency spectrum needs in China mobile communication

development.

The occupation of the IMT-2000 frequency spectrum in China is

illustrated in the following figure.

1850 1900 1950 2000 2050 2100 2150 2200 2250

ITU

1850 1900 1950 2000 2050 2100 2150 2200 2250

1880 MHz 1980 MHz

1885 MHz 2025 MHz

2010 MHz

IMT 2000

2170 MHz

IMT 20002110 MHz 2170 MHz

MSS MSS

China MSSMSS MSSFDDFDD

1920 MHz

TDD TDD

1850 1900 1950 2000 2050 2100 2150 2200 2250

ITU

1850 1900 1950 2000 2050 2100 2150 2200 2250

1880 MHz 1980 MHz

1885 MHz 2025 MHz

2010 MHz

IMT 2000

2170 MHz

IMT 20002110 MHz 2170 MHz

MSS MSS

China MSSMSS MSSFDDFDD

1920 MHz

TDD TDD

Figure 1-3 Occupation of the IMT-2000 frequency spectrum in China

The bands allocated for IMT-2000 in China are listed below:

1) Basic operating bands

FDD mode: 1920 MHz ~ 1980MHz/2110 MHz ~ 2170 MHz

TDD mode: 1880 MHz ~ 1920 MHz/2010 MHz ~ 2025 MHz

2) Supplementary operating bands

FDD mode: 1755 MHz ~ 1785 MHz/1850 MHz ~ 1880 MHz


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TDD mode: 2300 MHz ~ 2400 MHz, shared together with the wireless

location services; both are major services and the sharing standard is

to be specially formulated.

3) Operating band for satellite mobile communication systems

1980 MHz ~ 2010 MHz/2170 MHz ~ 2200 MHz.


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Chapter 1 Wcdma System Overview

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