Modified Exponential Companding for PAPR Reduction of OFDM Signals

In this paper, a new nonlinear companding technique, called the modified exponential companding technique, is proposed to reduce the peak to average power ratio (PAPR) of the orthogonal frequency division multiplexed (OFDM) signals. Instead of transforming the Rayleigh distributed OFDM signal into uniformly distributed signal as in the case of exponential companding proposed by Jiang, et al. (2005), we consider different probability distributions of the transformed signal, by introducing a control parameter a, which reduces the PAPR further. Simulation study demonstrates that the proposed method results in better PAPR reduction and improved BER performance compared to the exponential companding.