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112/04/09Fu-Jen Catholic

University Department of Electronic Engineering

Ch0: INTRODUCTION

0.1 Mobile communications 1st generation: analog voice service

AMPS(USA), Advances Mobile Phone Service, IS-54 NMTS(Europe), Nordic Mobile Telephone System TACS(England), Total Access Communication System NAMTS(Japan), NEC Advances Mobile Telephone System

2nd generation: voice and data service D-AMPS(USA), Digital-AMPS, IS-136 GSM(Europe), Global System for Mobile Communication DCS(England), Digital Cellular System PDC(Japan), Personal Digital Cellular CDMA(North American), IS-95

3rd generation: voice, data and multi-media service (2Mbps) 4th generation: voice, data and interactive-media service (156Mbps)



Ch0: INTRODUCTION

Quality of Service in old generations: Voice Quality (improved) , Coverage (world-wide seamless access) & Costs (low) Quality of Service aspects : low BER and low delay time

New Services and Capabilities in new generations Enabling new voice and data service that are not currently available with 1G and 2G

technology High bandwidth services (data, image, multimedia)



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Ch0: INTRODUCTION

0.2 Development of CDMA: Spread spectrum communications originate from MIT Lincoln Labs since 1920’s. The theory of spread spectrum communications has been well known since the late 1940's. It has been used somewhat intensively in the field of secure military communications since

1950's, but in commercial applications it is a relatively new technique. The spread spectrum technique has been released from military since 1970’s. The first major commercial application of spread spectrum techniques was the Global

Positioning System (GPS). R.G. Cooper and Nettleton proposed the North American DS-CDMA systems in 1977. It is

further commercialized by Qualcomm as narrowband CDMA(IS-95)



Ch0: INTRODUCTION

0.3 3G development history: In 1985 ITU (International Telecommunication Union) proposed the 3G specification,

which is called FPLMTS (Future Public Land Mobile Telecommunication Systems). In 1996 it is renamed as IMT-2000 (International Mobile Telecommunication) and defines the specifications 144K bps in fast moving speed 384K bps in walking, slow moving speed 2M bps in standstill environment

Proposals for 3G Standards Wideband-CDMA (Europe) CDMA-2000 (North American) TD-SCDMA (China)



Ch0: INTRODUCTION

W-CDMA: It is proposed by Ericsson (Sweden) and NTT DoCoMo (Japan) which is an extension of GSM systems. In 2001, The first W-CDMA 3G service is proposed in Japan by the DoCoMo company.

CDMA-2000It is an extension of narrowband CDMA (IS-95) CDMA-2000 1X, wideband service, 307K bps in 1.25M Hz BW CDMA-2000 3X, wideband service 2M bps in 5M Hz BW CDMA 2000 1X EV-DO CDMA one, narrowband service, 8 voices, 64K bps/channel In 2000, The telecommunication company in Korean proposed CDMA 2000 1X system

and the Samsung Electronics company propose a few types of CDMA-2000 1X handsets.

TD-SCDMAIt is the combination of TDMA system and synchronization CDMA, which is proposed by the Simens (Germany) and Datang (China) in 1999.



Ch0: INTRODUCTION

3G Telecommunication licenses Taiwan : A,B,C,D for W-CDMW at 2G Hz and E for CDMA2000 at 800M Hz. Japan: 2 for W-CDMA and 1 for CDMA2000 Korean: 3 for W-CDMA and 1 for CDMA2000

CDMAIS-95A IS-95B CDMA2000 1x

1x EV DO 1x EV DV CDMA20003GPP2

CDMA20003x/5MHz

GSM GPRS EDGE

WCDMA3GPP

1.44 kbps

9.6 kbps

64 kbps 144 kbps

56 kbps 384 kbps

PDC28.8 kbps

2.5G <384 kbps 3G ~2 Mbps2G <65 kbps

TDMA9.6 kbps

1999 2002

CDMA Evolution

TD-SCDMA3GPPc



Ch0: INTRODUCTION

0.4 International Telecommunication Union (ITU)

IMT-2000 : International Mobile Telecommunications 2000 the time schedule for the first trial system : year 2000 the frequency range to be used : around 2000 MHz

The International Telecommunication Union (ITU) is responsible for the IMT-2000 specification. The requirements for the 3G standardisation have been discussed under the term FPLMTS (Future

Public Land Mobile Telecommunications System) since the early 1990s. In the mid 1990s the term FPLMTS was changed to the term IMT-2000.

UMTS UMTS stands for Universal Mobile Telecommunications System UMTS is a member of the ITU‘s IMT-2000 global family of 3G mobile communication systems The European Telecommunication Standards Institute ETSI is responsible for the UMTS

standardization UMTS is the successor standard to the second generation GSM. UMTS will play a key role in creating the future mass market for high-quality wireless multimedia

communications that will approach 2 billion users worldwide by the year 2010



Ch0: INTRODUCTION

Seamless World-wide Access



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Air Interfaces for 3G



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Spectrum Allocation for 3G



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Evolutionary Path of GSM towards UMTS



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0.5 4G possible techniques W-CDMA with OFDM technique → Multi-Carrier CDMA LAS-CDMA (large area synchronization CDMA by China) Position CDMA 4G standards will be proposed in 2010 ( NTT DoCoMo plans to propose the 4G

standard in 2007).



Ch0: INTRODUCTION

0.6 Principles of spread spectrum systems :



Ch0: INTRODUCTION

The major applications of spread spectrum communications are

for military purpose, which requires ① Security or low probability of

interception

② Anti-jamming, anti-interference for commercial purpose, which requires

① Multiple access capability

② Anti-multipath fading Anti-jamming, anti-interference



Ch0: INTRODUCTION

Multiple access One of the most advantageous properties of spread spectrum technique is that it can be

very conveniently used as a multiple access method. In the traditional multiple access schemes, the fundamental resources are frequency

and time.① frequency division multiple access (FDMA) and

② time division multiple access (TDMA),.

In CDMA, multiple users are using the same frequency band at the same time (time and frequency overlap). The key elements are the used spreading codes and their properties.

Show a lot of block diagrams of CDMA systems in the following.



Ch0: INTRODUCTION Digital Communication Systems



Ch0: INTRODUCTION Digital Communication Systems and CDMA systems



Ch0: INTRODUCTION Text Book layout (Topics for CDMA systems)



Ch0: INTRODUCTION CDMA with QPSK Modulation Systems



Ch0: INTRODUCTION Uplink CDMA Systems



Ch0: INTRODUCTION Uplink CDMA Systems with multicode transmission



Ch0: INTRODUCTION Downlink CDMA Systems



Ch0: INTRODUCTION

0.7 Important Topics for CDMA network systems (physical layer)

1. PN sequences

2. Code acquisition

3. Code tracking

4. Modulation/demodulation

5. Power control

6. Adaptive CDMA networks

7. Radio channel

8. Multiuser detection

9. Advanced CDMA systems, MC-CDMA, OFDM



Ch0: INTRODUCTION

0.8 Reference

1. S.G. Glisic, “Adaptive WCDMA,” , Chapter 12. CDMD development group, http://www.cdg.org3. 3G Partnership Project 2 ， http://www.3gpp2.org/ 4. 3 G Partnership Project ， http://www.3gpp.org/5. 3G Today - IMT-2000 Standard ， http://www.3gtoday.com/index.html 6. CDMA2000 ， http://www.ericsson.com/ 7. Cellular Online ， http://www.cellular.co.za/main.htm 8. Cellular Technologies Of The World ， http://www.cellular.co.za/main.htm 9. Philips Consumer Communications ， http://www.wca.org/dgibson/index.htm 10. TDD White Paper ， http://www.tddcoalition.org/ 11. TD-SCDMA White Paper ， http://www.siemens-mobile.com/mobile 12. Wireless Web Features - TD-SCDMA and W-CDMA make ideal partners for

3G ， http://wireless.iop.org/ 13. UMTS World ， http://www.umtsworld.com/default.htm

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