【資料成文時(shí)間】：2004
【語(yǔ)言】：eng
【頁(yè)數(shù)】：67
【何人（公司）所著】：
【文件格式】：pdf
【文件原名】：
【摘要或目錄】：
What is CDMA? • What is IS-95? • How does CDMA work? What is IS-95? Lucent Technologies implementation of CDMA (as well as that of other equipment manufacturers) are based on a joint standard known as Interim Standard 95, or IS-95. The two standards bodies writing the standard are the EIA (Electronic Industries Association) and the TIA (Telecommunications Industries Association). This standard provides the basic framework or rules. Each equipment provider must provide some degree of interoperability between equipment of different manufacturers. For example, mobile phones manufactured by one company should work with another company’s base stations. How does CDMA work? CDMA uses unique digital codes, rather than separate RF frequencies or channels to differentiate users. Frequency divisions are still used, but in a much larger bandwidth (1.23 MHz). In CDMA, a single user’s channel consists of a specific frequency combined with a unique code. All users share the same range of radio spectrum. Advantages of CDMA • Increased Capacity • Multipath Usage • Soft Handoff • Built-in Degrees of Privacy • Cloning Protection • Lower Transmit Power Levels

[ 本帖最后由 spatial 于 2010-10-10 22:02 編輯 ]