Time domain statistical control for PAPR reduction in OFDM system

Abstract

This paper studies the problem of peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) system. It introduces a new PAPR reduction method that performs signal processing in the OFDM time domain. The simple non-linear amplitude pre-distortion process of the proposed method changes the statistical characteristics of the OFDM symbol from Rayleigh distribution into Gaussian like distribution. This change in statistical distribution is accompanied by changes of the peak and average power values and consequently reduces in the PAPR value. This scheme decreases the bit error rate (BER) slightly while significantly reduces the PAPR value. Furthermore, there is no need for side information, and hence no loss in the data rate. For the 64-QAM OFDM system with 512 sub-carriers, 4 dB reduction in PAPR value is achieved at only -15 dB spectral shoulder re- growth below the in-band signal level.