eeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Future Enhancements and Services Chapter 11 The Third Generation The 3G system can be viewed as two distinct elements: the Access Network (AN) and the Core Network (CN). These two elements have distinct func- tions and, as far as possible, are independent of each other. This is consis- tent with the family of technologies concept, which enables flexible interconnection between the CN and different access technologies. UMTS Terrestrial Radio Access Network (UTRAN) The ETSI decision in January 1998 on the radio access technique for UMTS combined two technologies-W-CDMA for paired spectrum bands and Time Division Duplex-CDMA (TD-CDMA) for unpaired bands-into one common standard. This powerful approach promises an optimum solution for all the different operating environments and service needs. The transmission rate capability of UTRA will provide at least 144 Kbps for full-mobility applica- tions in all environments; 384 Kbps for limited-mobility applications in the macro- and microcellular environments; and 2.048 Mbps for low-mobility applications particularly in the micro- and picocell environments. The 2.048-Mbps rate may also be available for short-range or packet applica- tions in the macrocellular environment, depending on deployment strate- gies, radio network planning, and spectrum availability. Multimode Second- Generation/UMTS Terminals UMTS terminals will exist in a world of multiple standards and this will enable operators to offer maximum capacity and coverage to their user base by combining UTRA with second- and other 3G standards. Therefore, oper- ators will need terminals that are able to interwork with legacy infrastruc- tures such as GSM/DCS1800 and Digital European Cordless Telephony (DECT) as well as other 2G worldwide standards such as those based on the U.S. AMPS standard, because they will initially have more complete coverage than UMTS. Many UMTS t