Transmit precoding aided spatial modulation for multi-user correlated large-scale MIMO channels

摘要

We propose a transmit preprocessing aided spatial modulation (PSM) scheme for downlink of multi-user multiple-input multiple-output (MIMO) systems which exploits the spatial correlation matrices of users. In this way, array antennas in base station can be scaled to large dimensions while requiring reduced dimension channel state information at transmitter (CSIT). This property makes proposed PSM suitable for large-scale MIMO frequency-division-duplexing (FDD) systems in order to decrease the downlink training and the CSIT feedback from users in uplink. In the proposed PSM effort, a zero forcing (ZF) based two-stage precoding is designed in which the first stage is pre-beamforming based on second-order statistics to reduce the impact of the multi-user interference and at the second stage a precoding is done by exploiting reduced dimension effective channel to enable successful signal detection at each receiver. Our simulation results show that the proposed multi-user PSM scheme succeeds in eliminating multi-user interference and detecting transmitted spatial symbol which improves in large-scale regimes.