Low Complexity OFDM Channel Estimation

Abstract

In this paper, we propose a new robust pilot-assisted channel estimation algorithm for OFDM in fast fading channel. Although least square (LS) channel estimator has low complexity, the performance is not suitable for practical case. On the other hands, linear minimum mean square error (LMMSE) channel estimator has good performance with very high complexity that is square of LS’s. In addition, the channel mismatch can degrade the performance of LMMSE. However, our proposed channel estimation algorithm requires just two times more than that of LS and it can achieve 5dB improvement in MSE over LS. The BER performance of proposed algorithm is close to LMMSE as windows size is increased. Also the proposed method is robust to the channel mismatch.