Message-passing detector for uplink massive MIMO systems based on energy spread transform

Abstract

This paper investigates low-complexity multi-user detectors for massive MIMO systems in practical channels. Beam domain message passing algorithm on the sparse-graph is proposed by exploiting the channel sparsity in beam domain, which has much lower computational complexity compared to the dense-graph based detections. As the massive MIMO channels are usually not i.i.d Gaussian distribution and central limit theorem (CLT) will no longer apply, conventional approximate message passing detector (AMP) may diverge. To improve the performance of AMP in practical channels, we further propose energy spread transform (EST) based massive MIMO transmission, which guarantee that the equivalent channels are i.i.d. distributed. Furthermore, by deriving the state evolution (SE) equations, the convergence analysis of the proposed detector is also provided. Simulation results show that, the proposed detector outperforms the conventional AMP and minimum mean square error (MMSE) detectors, and has fast convergence rate.