Improving Channel Estimation in OFDM Systems via Independent Component Analysis

In this paper the effect of CFO (carrier frequency offset) on channel estimation in OFDM systems is investigated. The LMMSE channel estimation is considered and it is shown that CFO degrades the performance of this algorithm. In addition a novel method called ICA-LMMSE is proposed. It uses ICA (independent component analysis) to find an estimate of CFO, in order to cancel out the inefficiency caused by CFO in the LMMSE channel estimation. It is shown that by applying the proposed method the MSE of the channel estimation algorithm is decreased to a high extent. The effectiveness of the method is also shown by simulation.