Clipping noise mitigation for pilot symbols in OFDM systems

Clipping is often used to reduce the large peak-to-average power ratio (PAPR) of orthogonal frequency-division multiplexing (OFDM) signals. However, it introduces additional noise which causes nonlinear distortion not only on data but also on pilot symbols. So for a pilot-aided OFDM system, clipping will degrade the channel estimation to influence system performance. In this paper, a new technique is proposed to mitigate clipping noise on pilot symbols, so channel estimation is improved. It is shown by simulation that the proposed method can significantly improve channel estimation and system performance.