Polynomial expansion detector for uniform linear arrays

In this paper, we design a low complexity linear MMSE decoder to recover the signal transmitted by M mobile users to a base station equipped with N receiving antennas, arranged as a uniform linear array (ULA). The angles of arrival are supposed to be uniformly distributed. As the dimension increases, it is hard to invert the system and therefore recent results on random matrix theory and polynomial expansion detectors are helpful to approximate the optimum linear MMSE receiver. Simulation results confirm the validity of this approximation.