Robust precoding scheme for multi-user MIMO visible light communication system

This paper considers a multi-user multiple-input multiple-output (MU-MIMO) visible light communication (VLC) interference channel. The multi-user interference (MUI) can be successfully eliminated with the perfect knowledge of channel state information (CSI). However, the perfect information may not be available at transmitter, which will lead to severe interference and consequently degrade the system performance. Robust precoding design with the assist of block diagonalization (BD) scheme is proposed to minimize the mean square error (MMSE), which not only completely suppresses the MUI but also maximizes the sum rate of the MU VLC system. Simulation results are presented to validate the effectiveness of the proposed algorithm.