Lattice-reduction-aided robust detection for MIMO systems with channel estimation error

Abstract

In recently years, lattice-reduction (LR) has been proposed to improve the performance of linear and successive interference cancellation (SIC) detectors in MIMO systems. It is proved that LR-aided linear detectors collect the same diversity order as that exploited by the ML detector but with much lower complexity when perfect channel state information (CSI) is available at receiver side. However, in practice, CSI is always contaminated by channel estimation error. In this paper, we proposed MMSE based LR-aided robust linear and SIC detection schemes which are capable of improving the BER performance in the context of channel estimation error. Additionally, we derived the approximate value of error floor as a function of channel estimation error and proved the BER improvements of robust LR-aided MMSE(-SIC) detector on traditional LR-aided MMSE(-SIC) detector increase with the growing number of transmit and receive antennas. Simulation results validate the conclusion.