of skill but time and chance happen to them all." Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Source: CDMA CAPACITY AND QUALITY OPTIMIZATION Chapter Worldwide CDMA Standards cdmaOne, originally American National Standards Institute (ANSI) Interim Standard 95 (IS-95), was the only second-generation (2G) code division multiple access (CDMA) standard for cellular telephony. With the advent of third generation (3G), CDMA has come into its own. cdma2000 was designed as the successor to cdmaOne, adding high- speed data capacity and improving a number of technical features. It is being deployed in North America in 2002. Wideband CDMA (W-CDMA) is the CDMA standard designed to be a successor to the Global System for Mobility (GSM) for the European market and other countries where GSM is already in place. There is also WCDMA without the hyphen, a general term for any wideband CDMA standard with 3.75 MHz of bandwidth or higher per carrier, three times the bandwidth of cdmaOne. With this terminology, both cdma2000 and W-CDMA would be types of WCDMA. 1 CDMA is constantly evolving. In fact, efforts to define a fourth-generation (4G) set of standards are already underway, as described in Part 9. The latest fully developed CDMA standard is, however, time division synchronized CDMA (TD-SCMA). The TD- SCDMA standard was developed too late to be considered for the United States and Europe, but the People's Republic of China, now the world's largest market for cellular telephones, has chosen to deploy a TD-SCDMA system. The effort behind the TD- SCDMA concept seems to be to create a successor to GSM that combines several multiple-access methods to achieve optimal capacity and optimal bandwidth flexibility. These standards are summarized in Table 10.1. Please note that some of the sum- mary information is provided in more precise detail later in the chapter.