Multi User Detection in CDMA System Using Linear and Nonlinear Detector

DS-Code division multiple access is considered as the third generation of cellular mobile used in interim standard 95(IS-95) and it is currently being standardized for Universal Mobile Telecommunication Systems (UMTS). CDMA offers attractive features, such as frequency reuse, soft handoff, increased capacity, and multipath combating. In a CDMA system, several users simultaneously transmit information over a common channel using pre-assigned codes. The conventional single user detector consists of a bank of filters matched to the spreading codes. This detector suffers from two problems. First, Multiple Access Interference (MAI) produced by the other co-channel users is a significant limitation to the capacity of this detector.