3.5 Third-Generation Mobile Networks
The development of third-generation (3G) mobile systems began when the World Administrative Radio Conference (WARC) at its 1992 meeting identified the frequencies around 2 GHz that were available. ITU (International Telecommunications Union) has recommended several different air interfaces for third-generation systems, based on either CDMA or TDMA technology. The IMT-2000 standards that define 3G air interfaces are as follows:
WCDMAWideband code division multiple access will be deployed in the Europe and Asia in the 2-GHz frequency spectrum.
EDGEEnhanced data rates for GSM evolution improves the spectral efficiency of the existing GSM frequencies.
1XRTT or cdma2000This is a multicarrier CDMA system that is designed to be deployed in the same frequency band as IS-95.
The Universal Mobile Telephony System (UMTS) is a third-generation mobile system. Standardization of UMTS has been done in the third-generation partnership project (3GPP) organization. UMTS is the evolution of second- generation GSM systems. The biggest change from second-generation to third-generation systems is that 3G systems will offer support for packet data services. 3G networks are expected to become extensions of the Internet and thereby enable the creation of the wireless Internet. With support for packet data built into the air interface as well as the core network, new types of applications and services for the mobile industry are expected to be developed. 3GPP2 is equivalent to the 3GPP organization and has developed an architecture based around cdma2000.
Third-generation mobile networks are in the process of being deployed now. Operators in Korea and Japan have taken the lead with these deployments. In the United States, cdma2000-based networks are now operational. Docomo in Japan is the first network operator to deploy WCDMA in a network known as FOMA (Freedom of Mobile Multimedia Access).
Descriptions of cdma2000 and UMTS networks are covered in Chapters 9 and 10.