CDMA2000, W-CDMA and IDMA : An Overview

Now-a-days, various multiple access schemes have attracted attention of researchers and have near Shannon limit performance in multi-user environment. Few of them are in application while others are under development for future application. This paper discusses the basic principals of these advanced multiple access schemes named CDMA2000, Wideband-CDMA (W-CDMA), and Interleave Division Multiple Access (IDMA) scheme. So, in this paper an overview of CDMA2000, W-CDMA, and IDMA is presented and also discuss the main features and areas of application as the future air interface access schemes for IMT-2000/UMTS