PERFORMANCE ANALYSIS OF MODULATION TECHNIQUES IN GA ASSISTED CDMA WIRELESS COMMUNICATION SYSTEM WITH AWGN RAYLEIGH FADING CHANNEL

摘要

The transmission from the base station to mobile or downlink transmission using 16-ary Quadrature Amplitude modulation (QAM), 64-ary QAM and Quadrature phase shift keying(QPSK) modulation schemes are considered in Code Division Multiple Access(CDMA) system. We have done the implementation and analysis of these modulation techniques when the system is subjected to Genetic algorithm (GA) for multiuser detection and Additive White Gaussian Noise (AWGN) with fading and Rayleigh fading d in the channel. The research has been performed by using simulation in MATLAB 7.7 and evaluation of Bit Error Rate (BER) against Signal-to-Noise Ratio (SNR) for CDMA system model. From analysis of three modulation techniques, the system could use more appropriate modulation technique to suit the channel quality, thus we can deliver the optimum and efficient data rate to mobile terminal.