Distributed differential evolution algorithm for PAPR reduction of OFDM signals

Abstract

Orthogonal frequency division multiplexing (OFDM) is a very powerful multicarrier scheme to mitigate frequency selective fading in wireless channels. However OFDM is affected by high peak to average power ratio (PAPR) conditions. A signal with high PAPR causes severe transmission problems due to the non linearity of high power amplifier (HPA) used at the transmitter end. One of the most promising methods proposed to reduce the PAPR consists of acting on the rotation phases of the OFDM symbols: this is known as the partial transmit sequence (PTS) method. Although this method achieves significant PAPR reduction, it requires an exhaustive search thus has a high computational complexity. To reduce this complexity, we propose in this paper a suboptimal algorithm based on distributed differential evolution algorithm (DDE) with self adaptation of the control parameters. The performance in PAPR reduction is close to that of the optimal case but with a significantly lower number of searches thus leading to a reduction in computational complexity.