Novel PAPR Reduction Scheme Based on Piecewise Nonlinear Companding Transform in OFDM Systems

In this letter, a novel nonlinear companding scheme is proposed to reduce the peak-to-average power ratio (PAPR) for orthogonal frequency division multiplexing (OFDM) systems with a low bit error rate (BER) and out-of-band (OOB) radiation of the power spectral density (PSD). This companding scheme does not change the statistics of small-amplitude signals and transforms the statistics of large amplitude signals into a sine function. The proposed scheme can maintain average signal-power constant by appropriately selecting the parameters. We also give the theoretical performance analysis for the proposed companding function. The simulation results indicate that the proposed companding scheme can effectively reduce the PAPR of OFDM systems with both low BER and OOB of PSD.