Robust Semi-blind Channel Estimation for MIMO Systems

Proposed is a novel Orthogonal Procrustes (OP) based semi-blind channel estimation method for multi-input, multi-output (MIMO) systems. The main idea of our technique is, using specific properties of the OP algorithm, to estimate the optimum rotation matrix from channel matrix instead of to estimate channel parameters directly. This results in substantially improved estimation accuracy. Furthermore, the introduced semi-blind scheme is shown to be very efficient when the number of the receive antennas is no less than the number of transmit antennas. Analytical expressions for the mean-square error (MSE) of the proposed algorithm are derived in closed forms. Various numerical examples show that our proposed algorithm can achieve the much better estimation accuracy than the existing LS technique.