Non-Linear Fuzzy Receivers for DS-CDMA
Communication System

Abstract

Direct sequence-code division multiple access (DS-CDMA) technique is used in cellular systems where users in the cell are separated from each other with their unique spreading codes. In recent times DS-CDMA has been used extensively. These systems suffers from multiple access interference (MAI) due to other users transmitting in the cell, channel inter symbol interference (ISI) due to multipath nature of channels in presence of additive white Gaussian noise (AWGN). This thesis presents an investigation on design of fuzzy based receivers for DS-CDMA system. Fuzzy based receiver has been proposed to work as chip level based (CLB) receivers and also multi user detection (MUD) receivers. It is seen that fuzzy receiver is capable of providing performance close to optimal radial basis function (RBF) receivers and provide considerable computational complexity reduction. Extensive simulation studies demonstrate the performance of the fuzzy receivers and the performance have been compared with RAKE receiver, matched filter (MF) receiver, minimum mean square error (MMSE) receiver and RBF receiver.