Blind channel estimation in MIMO-OFDM systems

MIMO-OFDM is one of the promising scheme for achieving high data rate and large system capacity over wireless networks. In this paper, we investigate the blind channel estimation in MIMO-OFDM systems based on the noise subspace method. We exploit the cyclostationarity induced by OFDM with cyclic prefix. The sufficient identifiability conditions were established, and the noise subspace algorithm was developed for MIMO-OFDM channel estimation. The algorithm only requires knowledge of the upper bound on the channel length, it does not impose restrictions on channel zeros and it exhibits low sensitivity to stationary noise. Finally, we demonstrate validity of the algorithm presented in this paper by Monte Carlo simulations.