Robust Channel Estimation Resisting Symbol Timing Offset by MMSE Interpolation for OFDM System

In pilot-aided OFDM systems, the minimum mean-square-error (MMSE) interpolator provides the optimum performance based on the channel statistics. And symbol timing offset (STO) introduces a linear phase rotation to data modulated on individual subcarriers. A MMSE channel estimator designed only using the wireless channel statistics performs only sub-optimally when subcarrier phase rotations due to STO are present. In this paper, we show that the performance of the channel estimation can be retained by using the modified MMSE interpolator when the STO exists. Simulation results show that the bit error rate (BER) performance degradation due to STO can be neglectable by the reform interpolation technique.