Enhanced Clipping and Filtering With WFRFT for PAPR Reduction in OFDM Systems

Abstract

The major drawback of orthogonal frequency division multiplexing (OFDM) systems is the high peak-to-average power ratio (PAPR) problem. Some PAPR reduction methods have been proposed in the literature, and clipping and filtering (CAF) has been recognized as the simplest one. However, the CAF method introduces in-band distortion. In this paper, weighted fractional Fourier transform (WFRFT) is utilized to enhance the CAF method to improve the PAPR performance and mitigate the in-band distortion, which is called WFRFT-CAF method. The proposed WFRFT-CAF method is compared with existing PAPR reduction methods, based on computation complexity, PAPR reduction capacity, power spectral density (PSD), and bit error rate (BER) performance. Through simulations, it is validated that the WFRFT-CAF method can obtain better PAPR and BER performance than existing PAPR reduction methods considering the transmit power gain and path loss.