Iterative Channel Estimation for SISO and MIMO-OFDM Systems in Time-Varying Channels

Abstract—This paper proposes a simple and efficient algorithm using polynomial interpolation for SISO and MIMO-OFDM systems in a fast time-varying channel. The time averages of the multipath complex gains, over the effective duration of each OFDM symbol, are estimated using LS criterion. After that, the time variation of the channel within several OFDM symbols are obtained by interpolating the time average values using polynomial interpolation. Specifically, we propose and evaluate the performance of channel estimation using third-degree polynomial interpolation with an adaptive pilot scheme in order to optimally use pilot tones over time varying channels. The ICI can be cancelled by using partial successive interference cancellation (PSIC) in data symbol detection instead of basic SIC method. KeywordsChannel estimation, OFDM, MIMO, Mobile multipath channel.