Swarm Intelligence Applied to 16-QAM DS-CDMA Multiuser Detectors

In this paper, the uplink direct sequence code division multiple access (DS-CDMA) multiuser detection problem (M U D) with 16-QAM modulation in flat Rayleigh channel with spatial diversity is studied into a heuristic perspective, named particle swarm optimization (PSO). A parameter optimization procedure for the PSO applied to M U D problem, regarding the acceleration coefficients (φ 1 and φ 2 ), is provided, which represents the major contribution of this paper. Simulation results show that, after convergence, the performance reached by the PSO-M U D is much better than the conventional detector, and somewhat close to the single user bound (SuB) for not so high system loading.