Decision Aided Channel Estimation in Clipped OFDM

Clipping is a popular and simple method to overcome large peak-to-average power ratio (PAPR) in orthogonal frequency-division multiplexing (OFDM) systems, but it results in a nonlinear distortion, which degrades the performance of channel estimation and signal detection. In this paper, clipping effect on channel estimation is analyzed, a decision-aided channel estimation method to mitigate the clipping distortion is developed and its potential gain in channel estimation is derived. The gain can be obtained by an iterative channel estimation and signal detection process. Theoretical and simulation results show that the decision aided method can effectively improve the performance of channel estimation in clipped OFDM.