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Chapter 1 Wcdma System Overview
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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.
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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.
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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.
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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
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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.
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Basic Principles of WCDMA System WCDMA System Overview
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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Basic Principles of WCDMA System WCDMA System Overview
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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