An effective hybrid GACSA -based multi-user detection for ultra-wideBand communications systems

In this paper, we investigate the performance of various interference cancellation techniques in direct-sequence ultra-wideband (DS-UWB) communication systems. Multiple access interference (MAI) causes the performance of the conventional single user detector in DS-UWB systems to degrade. Due to high complexity of the optimum multiuser detector, suboptimal multiuser detectors with less complexity and reasonable performance have received considerable attention. A hybrid approach that employs a genetic algorithm (GA) and chaos algorithm (CSA) for the MUD problem in UWB communication systems is proposed. By taking advantage of heuristic values and the collective intelligence of GACSA, the proposed detector offers almost the same bit error rate (BER) performance as the full-search-based optimum multiuser detector does, while greatly reducing the computational complexity. The near-far resistance of the GACSA-based multiuser detector is also examined. The good behavior of the proposed approach is demonstrated by means of comparisons in term of bit error rate (BER) performance and implementation complexity with the classical Rake receiver and different multiuser receivers previously proposed in the literature on this subject.