Detection of Nonlinearly Distorted OFDM Signals via Generalized Approximate Message Passing

In this paper, we propose a practical receiver for multicarrier signals subjected to a strong memoryless nonlinearity. The receiver design is based on a generalized approximate message passing (GAMP) framework, and this allows realtime algorithm implementation in software or hardware with moderate complexity. We demonstrate that the proposed receiver can provide more than a 2dB gain compared with an ideal uncoded linear OFDM transmission at a BER range 10÷10 in the AWGN channel, when the OFDM signal is subjected to clipping nonlinearity and the crest-factor of the clipped waveform is only 1.9dB. Simulation results also demonstrate that the proposed receiver provides significant performance gain in frequency-selective multipath channels.