Doubly Selective Fading Channel Tracking Based on Particle Filter in MIMO-OFDM Systems

Time selectivity and frequency selectivity are the main characteristics of wireless communication channels. To track doubly selective fading channels in MIMO-OFDM systems, a novel channel estimation algorithm based on particle filter is proposed. We model the fading channel as an autoregressive (AR) process and encode the transmit signal using space-time block code (STBC) scheme. In the receiver, channel estimation and symbol detection are alternated, and maximum likelihood (ML) scheme is used for symbol detection. Simulation results show that the proposed method has more effective tracking performance than traditional methods based on training symbols and offers much improved spectral efficiency.