Smart Phone and Next Generation Mobile Computing

Supporting Wireless Technologies 137

3.6 GSM Versus CDMA

The two major 2G cellular systems are not compatible with each

other. GSM and CDMA networks are both widely used worldwide.

For example, in the United States, Verizon Wireless, Sprint PCS, and

ALLTEL are CDMA operators, whereas Cingular Wireless, AT&T Wire-

less (merged with Cingular in 2004), and T-Mobile USA are GSM

operators. Another wireless operator, Nextel, uses iDEN, a TDMA

technology developed by Motorola. While the Europeans enjoy

continent-wide, GSM-dominated wireless services, the world’s largest

mobile wireless market, China, with a total number of about

398 million subscribers as of 2005 (source: Computer Industry

Almanac Inc.), is basically shared by two companies: China Telecom,