A hybrid companding transform technique for PAPR reduction of OFDM signals

Abstract

Orthogonal Frequency Division Multiplexing (OFDM) is an attractive technique for wireless communication applications. However, an OFDM signal has a large Peak-to-Average Power Ratio (PAPR), which can result in significant distortion when passed through a nonlinear device, such as a transmitter power amplifier. Number of techniques has been proposed for reducing the PAPR in OFDM systems. Among them Companding is a well-known technique for the PAPR reduction of OFDM signals. Recently, a piecewise linear companding technique is proposed to extenuate companding distortion. In this paper, a joint piecewise linear companding technique and Discrete Cosine transform (DCT) method is proposed to reduce peak-to-average of OFDM signal. Simulation results show that the proposed technique may obtain significant PAPR reduction while maintaining good performance in the Bit Error Rate (BER) and Power Spectral Density (PSD) compared to piecewise linear companding technique.