Per-Chip Multi-User Detection for SFH/BPSK Systems

In frequency-hopping systems, the multiple-access interference (MAI) occurs when more than one user appear on the same frequency at the same time. In this paper, we address the multi-user detection (MUD) problem for slow frequencyhopping (SFH) system with binary phase shift keying (BPSK). We first built a MAI model taking the hopping patterns and the phase offset into account, whereby the MAI is considered as independent yet unnecessarily identically distributed random variable. Under the proposed model, we further simplify the MAI by exploiting the Lyapunov central limit theorem and propose an iterative per-chip multiuser detection (PC-MUD) algorithm. By simulations, it´s verified that the performance of proposed algorithm is near to the performance of single user bound in additive white Gaussian noise environment.