Joint Precoding and Decoding in MU-MIMO Downlink Systems with Perfect Channel State Information (CSI)

In this paper, we propose an joint optimization of precoder and decoder for downlink transmissions in multiuser multiple-input, multiple-output (MU-MIMO) systems with perfect channel state information (CSI). This paper focuses on the scenario when an improper constellation such as binary phase shift-keying (BPSK) or M-ary amplitude shift-keying (M-ASK) is employed. The proposed joint design aims to minimize all the users total mean-squared-error (TMSE) under the constraint of total transmit power. Simulation results show that the proposed joint linear precoder and decoder designs improves BER performance of MU-MIMO downlink systems and verify its effectiveness.