cdma2000 RF measurements With Tektronix WCA200A Series Wireless Communication Analyzers

cdma2000 systems offer the promise of both superior transmission efficiency and excellent sound quality for a large subscriber base, while being cost effective. This advanced technology, however, requires new RF measurement functionality that conventional tools may not be able to deliver. This application note provides a technical overview of cdma2000, a summary of the RF measurements required by the specification, and a discussion of how Tektronix' WCA200A Series Wireless Communication Analyzers are used to make those measurements.

The Code Division Multiple Access (CDMA) specification provides an important pathway to third-generation (3G) global wireless communication systems. Designed to accommodate the increasing number of subscribers and faster communication speeds required by today's wireless communications, cdma2000 systems also provide the data transmission capabilities needed for Internet connection services. With voice and character transmission services for music and image transmissions, the specification meets the requirements of a multimedia service, providing capacity for features such as networked gaming through the Internet.

Technical Overview

cdma2000 evolved from the cmdaOne standard under the guidance of the Third Generation Partnership Project 2 (3GPP2). Originating in North America, cdma2000 technology has been adopted around the globe and is the first third generation technology to be deployed.

cdma2000 is being introduced in three phases. The first phase (cdma2000 1x) provides a data communication service at 144 kbps. The chip rate is 1.2288 Mcps, which is exactly the same as the earlier IS-95 rate. The second phase includes cdma2000 1xEV-DV and 1xEV-DO, which use an additional time domain component to increase data rates within a 1.25 MHz carrier and provide high rate data packet services to meet the demands of high-speed web or mail downloading. The third phase (cdma2000 3x) specifies 256 Walsh codes and accommodates three adjacent 1.25 MHz carriers (to remain backward compatible with cdmaOne).