A new modified genetic algorithm for multiuser detection in DS/CDMA systems

Abstract

The conventional single user detector in DS-CDMA (direct sequence code division multiple access) systems involves multiple access interference and the near-far effect which cause the limitation of capacity. On the other hand, the computational complexity of the optimum multiuser detector grows exponentially with the number of users. There has been a lot of interest in suboptimal multiuser detectors with less complexity and reasonable performance. In this paper we apply the classic and new modified genetic algorithms for multiuser detection of DS/CDMA signals. It is shown that the classic genetic algorithm (GA) reaches an error floor at high signal to noise ratios while the proposed method has higher performance than the classic one and is comparable to the optimum single user detector with much less complexity than the optimum multiuser detector.