Subspace based channel estimation in MIMO-OFDM systems [mobile radio applications]

A blind channel identification problem, based on exploiting the presence of a virtual carrier, is investigated for MIMO-OFDM systems. Sufficient identifiability conditions are established for the MIMO-OFDM channel to be identifiable up to a unitary matrix. And the subspace blind channel identification method is proposed. The method is attractive for its potential to increase the system's channel utilization due to the elimination of the cyclic prefix. Computer simulation results are finally provided to illustrate the effectiveness of the proposed blind channel identification method.