Channel estimation and ICI cancellation for high mobility pilot-aided MIMO-OFDM systems

In this paper, we propose an iterative channel estimation and inter-carrier interference (ICI) cancellation method for highly mobile users in Long-Term-Evolution (LTE) systems. The proposed scheme estimates the wireless channel by using pilot symbols, estimates of the data symbols and Doppler spread information at the receiver. The wireless channel is expressed by a weighted time-domain channel interpolation, where the interpolation weights are designed based on the Doppler spread. The channel estimates are obtained by employing a least square (LS) method. A simplified parallel interference cancellation (PIC) scheme coupled with decision statistical combining (DSC) is used to cancel the ICI and to improve the data symbols detection. These data symbols are then utilized to refine the channel estimation further, iteratively. Simulation results are used to verify the effectiveness of the proposed method.