Channel estimation method based on channel order estimation for MIMO-OFDM systems

Multiple-input-multiple-output Orthogonal frequency division multiplexing (MIMO-OFDM) systems promise to provide significant increase in systems capacity for future wireless communication systems. The channel state information is required to achieve high capacity of MIMO-OFDM systems. In this letter, an effective channel order estimation method is proposed, which is robust to noise and Rayleigh exponential fading channel, and then an enhanced channel estimation scheme is designed for MIMO-OFDM systems by making full use of training sequence and Cyclic prefix (CP). The method improves the performance of the channel estimator since the redundancy information in CP is used. Also, the theoretical Mean square error (MSE) bound of the enhanced estimator is derived. Simulation results of MIMO-OFDM systems with two transmit and two receive antennas demonstrate the effectiveness of the algorithm. The performances of MSE and BER are enhanced.