A Novel Joint Precoder and Receiver Design with Imperfect CSI for Multi-User MIMO Downlink

This paper studies the design of a linear precoder and receiver for the downlink of multi-user multiple-input multiple-output (MIMO) systems with imperfect channel state information (CSI). First, we modify the regularized block diagonalization scheme for the case of imperfect CSI, where we assume the variance of the channel estimation error is known. Next, we propose a novel joint design for the optimized precoder and receiver pair based on the minimum mean square error (MMSE) criterion, where we introduce two transmit channel matrices designed for high signal-to-noise ratio conditions. We compare the performance of these schemes with the generalized MMSE channel inversion filtering via numerical analysis. The results demonstrate the superiority of our joint precoder and receiver design.