Multiuser detection using a genetic algorithm in CDMA communications systems

In this study, a hybrid approach that employs a genetic algorithm (GA) and a multistage detector (MSD) for the multiuser detection problem in a code-division multiple-access communications system is proposed. Using this approach: (1) the GA is used as the first stage of the MSD to provide a good initial point for successive stages of the MSD and (2) the MSD is embedded into the GA as a "genetic operator" to improve further the fitness of the population at each generation. Such a hybridization of the GA with the MSD reduces its computational complexity by providing faster convergence. In addition, a better initial data estimate supplied by the GA improves the performance of the MSD, and the embedded MSD improves the performance of the GA. Simulation results for the synchronous and asynchronous cases are provided to show that the approach is promising.