Channel estimation algorithms for broadband MIMO-OFDM sparse channel

In the broadband communication, channel impulse response usually exhibits sparse behavior (i.e.. many nearly zero taps). This paper considers the channel estimation of the sparse channel for broadband multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) systems. Three algorithms for MIMO-OFDM sparse channel estimation are presented and compared: least square channel estimation (LSCE), constraint least square channel estimation (CLSCE) with ideal delay estimation, matching pursuit based channel estimation (MPCE). Mean square error (MSE) performances an also analyzed. Simulation results show that MPCK has better performance than LSCE and is very close to CLSCE under the high SNR, and also MPCE does not require the a priori of channel. Using the MP-based channel estimator, the detection performance is nearly optimal.