Performance Analysis and Comparison of Spreading Codes in Linear Multi-User Detectors for DS-CDMA System

Direct Sequence Code Division Multiple Access (DS-CDMA) system is well known wireless technology. This system suffers from MAI (Multiple Access Interference) caused by Direct Sequence users. Multi-User Detection schemes were introduced to detect the users’ data in presence of MAI. Linear Multi-user Detectors and conventional Matched Filter (MF) are simulated using PN and even kasami sequences as spreading codes in DS-CDMA system. In this paper odd kasami sequence is proposed. For this, odd kasami sequence of length L=2 m which inclusive of initial bit, The Bit Error Rate (BER) performance of MMSE Detector provides better than Decorrelating detector and conventional Matched filter. Comparative Study shows that the proposed odd kasami sequence is better performed than PN and even kasami sequences in linear Multi-user Detectors and conventional Matched Filter (MF). Key-words— Multi-user detection, Matched filter, Decorrelating detector, MMSE, DS-CDMA, PN sequence, even kasami sequence and odd kasami sequence.