WCDMA AND WLAN FOR 3G AND BEYOND

1. WCDMA AND WLAN FOR 3G AND BEYOND 通訊所 研二 691430042 楊川民

2. Outline • Introduction • Glossary • UTRAN FDD Mode: WCDMA • UTRAN TDD Mode: TD/CDMA • WCDMA Evolution From 2G to 3G • Three Phases From Release 99 and Release 4 to Beyond 3G • Conclusion

3. Introduction

4. Glossary • FDD: Frequency Division Duplexing • WCDMA: Wideband Code Division Multiple Access • TDD: Time Division Duplexing • TD/CDMA: Time Division / Code Division Multiple Access • GSM: Global System for Mobile Communications • 3GPP: Third Generation Project Partnership • HSDPA: High Speed Downlink Packet Access • HS-DSCH: High Speed Downlink Shared Channel • UMTS: Universal Mobile Telecommunications System

5. UTRAN FDD Mode: WCDMA

6. UTRAN FDD Mode: WCDMA (cont.) • Figure 2.1 illustrates some of the UTRA Frequency Division Duplexing (FDD) characteristics. • This mode uses Wide-band Direct-Sequence Code Division Multiple Access (DS-CDMA), denoted WCDMA. • To support bit rates up to 2 Mbps, it utilizes a variable spreading factor and multi-code links.

7. UTRAN TDD Mode: TD/CDMA

8. UTRAN TDD Mode: TD/CDMA (cont.) • The 2nd UTRA mode results from the combination of TDMA–FDMA and exploits spreading as part of its CDMA component • It operates in Time Division Duplexing (TDD) using the same frequency channel • In this mode, the MSs can only access a Frequency Division Multiplexing (FDM) channel at specific times and only for a specific period of time • Hence, in the TDD mode we define a physical channel by a code, one TS, and one frequency, where each TS can be assigned to either the uplink or the downlink depending on the demand

9. WCDMA Evolution From 2G to 3G • WCDMA • support of multiple simultaneous service • Higher data rate than GSM • GSM • Not support of multiple simultaneous service • evolution parallel with WCDMA

10. Three Phases From Release 99 and Release 4 to Beyond 3G • Phase 1: High-Speed Downlink Packet Access (complete in 2001) • HS-DSCH, inherit many of the features of the DSCH defined in release 99 • Main proposed technical enhancement • Adaptive Modulation and Coding (AMC) • Fast Hybrid Automatic Repeat Request (FHARQ) • Fast Cell Selection (FCS) • HSDPA, released as part of release 4, completed in release 5

11. Three Phases From Release 99 and Release 4 to Beyond 3G (Cont.) • Phase 2: Uplink High-Speed Data, High-Speed Access for TDD (not approved) • Emphasisair interface optimization in the area of downlink high-data-rate support and attention uplink • Phase 3: Capacity Improvements in Uplink and Downlink, and Further Data Rate Enhancement (not approved) • Some of the foreseen air interface technologies become mature in a timeframe that may be unacceptable for the proposed phases 1 and 2 of WCDMA development

12. Future Challenge in WCDMA and WLAN • Data-intensive application need high data rate environment • How spreads bandwidth in new frequency allocations • How used to mobile business • Established roaming agreements for WLAN network subscriber management

13. Other Tread in the Next-Generation • Mobile business need an efficient way to access corporate information systems and databases remotely through the Internet backbone • Cover the demand for data-intensive applications and enable smooth online access to corporate data services in hot spots

14. Potential in WCDMA and WLAN • In hot spot environments • Application and service that need high data rate • In business environment • E-commerce • Fee service • In UMTS and UTRAN • Used WCDMA FDD and TDD achieve larger cell size and cost saving

15. Coupling of Air Interface

16. Beyond 3G to 4G • Issue in 3G evolution • It need to support IP and IP-based multimedia • 4G is a revolution of the air interface rather than a new phase of evolution • They have different access method

17. The Revolution Toward 4G

18. Conclusion • The WCDMA air interface is seen to develop far beyond its initial capabilities to satisfy future service and application needs • No time to fine answer that can overcome the issue in 3G, we want to fine in 4G