MULTIUSER DETECTION USING TGA-BASED PARTIAL PARALLEL INTERFERENCE CANCELLATION FOR CDMA SYSTEMS

Conventional multistage multiuser detectors such as parallel interference cancellation (PIC) suffer from error propagation. Therefore, in this paper, we proposed an adaptive multistage Taguchi-Genetic-Algorithm (TGA) fuzzy-based PIC multi-user detector for direct-sequence code-division multiple-access (DS-CDMA) systems over additive white Gaussian noise (AWGN) channel and Rayleigh fading channel. Simulation results show that the proposed TGA fuzzy-based PIC multiuser detector not only can find an optimal partial cancellation weight (PCW) for the multistage PIC multiuser detector by using the measured signal-noise ratio (SNR) and signal’s amplitudes, which reveal the reliability of the received signals but also can obtain both better performance and more robust results than the other detectors used in DS-CDMA systems. Furthermore, the TGA fuzzy-based PIC multi-user detector offers robust resistance against the near-far effect in DS-CDMA systems and always converges to the optimum solution with a small number of search stages.