An Enhanced Partial Transmit Sequence Segmentation Schemes to Reduce the PAPR in OFDM Systems

Abstract

Although the orthogonal frequency division multiplexing system (OFDM) is widely used in high-speed data rate wire and wireless environment, the peak-to- average-power-ratio (PAPR) is one of its major obstacles for the real applications. The high PAPR value leads some devices of the OFDM system such as power amplifiers and analog to digital converters to work out of band of these devices. Thus the system efficiency is degraded. Many techniques have been proposed to overcome the high PAPR in OFDM systems such as partial transmit sequences (PTS), selected mapping and interleaving technique. PTS is considered as one of the effective PAPR reduction methods; this scheme depends on segmentation of the input data into several subblocks and then combined again. The three well-known segmentation schemes are pseudo-random, adjacent and interleaving; each scheme has PAPR reduction performance, and computational complexity differs from one to another. In this paper, five types of segmentation schemes are proposed to improve the PAPR reduction execution including sine and cosine shape as well as hybrid interleaving and adjacent schemes in new approaches. From the simulation results, the proposed methods can achieve PAPR reduction performance greater than that of the adjacent and interleaving partition schemes, without increasing the computational complexity of the system. Moreover, the enhanced schemes can realize better PAPR performance with any number of subcarriers.