Interference cancellation for HNNPSO multiuser detection of UWB systems over multipath fading channel

The problem of multiple access interference (MAI) and inter-symbol interference (ISI) suppression in direct-sequence ultra-wideband (DS-UWB) systems is considered. This paper is dedicated to the application of intelligence computational techniques based on bionics to solve the difficult issue of multiuser detection (MUD) design capable of canceling the so-called MAI to reach low bit error rate (BER) with acceptable computation complexity. We apply the stochastic algorithm that employs a Hopfield neural network (HNN) and particle swarm optimization (PSO) for the MUD problem in DS-UWB system. The use of the HNN embedded PSO (HNNPSO) technique for multiuser detection is a novel ideal, and it leads to efficient techniques that can find a satisfactory solution by maximizing likelihood (ML) function in a small number of iterations. The computer experiments showed that the proposed HNNPSO technique not only can find optimal or close-to-optimal solutions but also obtain both better and more robust results than the existing algorithm reported recently in this literature.