Tap-Configured Time-Domain Precoder for MIMO-OFDM Systems with Channel Estimation Errors

Leveraging the correlation in the frequency domain is essential for channel estimation in a multi-input multi-output orthogonal frequency division multiplexing (MIMO-OFDM) system. However, precoding can impair the channel correlation, making channel estimation more challenging. This paper proposes a space-time estimator mismatch compensation precoding (ST-EMCP) method to maximize spectral efficiency. This approach explicitly introduces the mismatch between the estimator and the true channel, modeling the resulting estimation errors as interference and compensating for the mismatch within the framework of sum-rate maximization. By utilizing space-time precoding, ST-EMCP ensures the smoothness of the frequencydomain channel and compensates uniformly for the channel estimation mismatch across the entire frequency band, ultimately reducing the overall channel estimation error. Numerical simulations demonstrate that the proposed ST-EMCP achieves better channel estimation and higher throughput than existing methods.