Robust Recursive Two-Dimensional Channel Estimators for the MIMO-OFDM Systems

MIMO-OFDM systems operating in the wireless doubly-selective channels rely on the pilot-assisted transmissions to acquire channel state information. Application of the two-dimensional filtering algorithms to channel estimation in the MIMO configurations is challenging due to the complexity considerations. Furthermore, different pilot structures employed in different spatial links necessitate development of scalable and reconfigurable estimator structures. The estimation scheme should also be robust to the changes in channel statistics and operation mode restrictions. To address these problems, robust estimator architecture is presented, which is based on the transform-domain processing and separable adaptive filtering modules.