Abstract: A robust vector-precoding (VP) algorithm based on geometric mean decomposition (GMD) method was proposed for multiple input multiple output (MIMO) system with imperfect channel state information (CSI). By exploiting statistical information of CSI and minimizing the mean square error of signal vectors transmitted and received, the optimal perturbation vector and precoding matrix based on GMD method were got. The simulation results show that the proposed robust GMD-VP scheme outperforms the existing methods. The performance gain is at least 2dB at high SNRs.

Key words: multiple input multiple output(MIMO), imperfect channel state information, geometric mean decomposition, vector precoding