Efficient Decision-Directed Channel Estimation for OFDM Systems with Transmit Diversity

To reduce the complexity involved in decision-directed channel estimation (DDCE) in orthogonal frequency-division multiplexing (OFDM) systems with transmit diversity, both data decoupling and direct cancellation of inter-antenna interference (IAI) suffer from residual IAI caused by channel frequency selectivity and time selectivity. In this paper, we propose a new algorithm to improve the performance of low complexity DDCE in OFDM systems with transmit diversity. The proposed algorithm includes a new data decoupling scheme with weaker assumptions regarding channel frequency response, and residual IAI cancellation using the results of the DDCE. Simulation results demonstrate that the proposed algorithm improves the performance of MSE and BER considerably.