Interference compensation scheme using time domain replica signals for SP-MIMO/OFDM under large delay spread channel greater than GI

In mobile communications, MIMO-OFDM transmission performance suffers severe degradation caused by the large delay spread channel greater than guard interval (GI). This is because the excess delay results in considerable inter-symbol interference (ISI) between adjacent symbols and inter-carrier-interference (ICI) among subcarrier in the same symbol. In the case of scattered pilot (SP), the interference of pilot signals causes the deterioration of channel estimation. In this paper, we propose the interference compensation scheme using the time domain replica signals.We make the time domain replica signals from detected signals and the excess channel impulse responses over GI. After compensation of the time domain replica signals and the received signals, we recalculate the channel state information (CSI) and the CSI is updated. Finally, we carry out the channel compensation with updated CSI for obtaining an accurate compensated signals.