Low Complexity Polynomial-Model-Based Channel Estimation for MIMO-OFDM Systems

MIMO-OFDM is a promising technique for broadband communications over mobile wireless channel. In this paper, we investigate the channel estimation problem for MIMO-OFDM systems. We proposed an EM-based method to implement channel estimation, in which the polynomial channel model was used. The proposed EM-based method partition the problem of estimating a multi-input channel into independent channel estimations for each transmit-receive antenna pair, thus, avoid the matrix inversion encountered in polynomial model based estimation. Therefore, compared with polynomial model based method, the proposed method has an advantage of computational complexity without loss of estimation accuracy.