Iterative Clipping Noise Recovery of OFDM Signals Based on Compressed Sensing

摘要

The simple method of clipping is widely used to reduce the peak-to-average power ratio of orthogonal frequency division multiplexing (OFDM) signal prior to passing it through the high power amplifier (HPA). However, clipping is a nonlinear process that causes both in-band and out-of-band distortions. Filtering the clipped OFDM signal can eliminate the out-of-band distortion but it can lead to peak regrowth. Therefore, iterative clipping and filtering have been used to both remove the out-of-band interference and suppress the regrowth of the peak power. However, the iterative process will degrade the bit error rate performance further. In this paper, we proposed a semi-analytic scheme based on compressed sensing to reconstruct the iterative clipping noise. Moreover, the proposed scheme is also applicable for reconstructing the total nonlinear distortion of a system so that the OFDM signal passes both the clipper and HPA. Simulation results show that the proposed scheme performs well and the nonlinear distortion can be recovered effectively.