Implementation of low-complexity companding technique for efficient peak-to-average power ratio reduction in orthogonal frequency division multiplexing systems

Abstract

Orthogonal frequency division multiplexing (OFDM) system has become an extremely popular wireless communication system in recent years. However, since the OFDM system is limited by a high peak-to-average power ratio (PAPR), companding techniques are often used to reduce PAPR. A uniformly distributed non-linear companding scheme offers efficient PAPR reduction with a low bit error rate (BER). However, such a scheme is difficult to implement. This work presents the referred companding scheme, expanded as a Taylor polynomial. Further, a novel low-complexity companding technique is developed to simplify the Taylor polynomial scheme by using the Pade approximation. Simulation results indicate that the performance of the proposed scheme is nearly the same as that of the referred scheme and the Taylor polynomial scheme over the additive white Gaussian noise (AWGN) channel or the multipath fading channel. Furthermore, the results of the hardware implementation demonstrate that the proposed scheme has lower complexity and computational time than the referred and Taylor polynomial schemes.