A Modified RLS Channel Estimation Method in MIMO-OFDM Systems

The modified recursion lest squares (RLS) channel estimation method exploits preamble training sequences and adaptive forgetting factor to estimate channel state parameters without any prior statistics knowledge of channel in multiple input multiple outputorthogonal frequency division multiplexing (MIMO-OFDM) systems. Simulation results confirm that the RLS channel estimation method with adaptive forgetting factor (RLS-A) outperforms that with conventional forgetting factor (RLS-C) or with two-step forgetting factor (RLS-T) in both estimation accuracy and robustness. Therefore, the modified RLS channel estimation method can satisfy the requirement of the receiver for MIMO-OFDM systems.