Research On Peak-to-Average Power Ratio Reduction Algorithm For OFDM System

Orthogonal Frequency Division Multiplexing(OFDM)technology,which is the core technology of the fourth generation mobile communication system,is developed from Multi-Carrier Modulation(MCM).Because of its robustness to muti-path fading and narrowband interference suppression,the OFDM system is the most widely used Multi-Carrier transmission scheme in wireless communication system.However,although the OFDM system has better spectrum utilization,one major drawback of OFDM system is the High peak-to-average power ratio(PAPR).When the signal with high PAPR pass through a high-power amplifier(HPA)at the transmitter,some of the signal will come into the nonlinear region of the HPA,which will cause out of band radiation and in band distortion,resulting in performance degradation.Therefore,how to reduce the PAPR of OFDM system is an urgent problem to be solved.This article based on the existing suppression technology.At the first,we analyze several mainly types of inhibition of OFDM PAPR system,especially the clipping technique and partial transmit sequence(PTS)technique is discussed in detail,and conclude the merits and demerits of these methods.Finally,we find that traditional limiting technology can effectively decrease PAPR,but at the expense of the BER performance for the price.In order to solve this problem,we proposed improve clipping algorithm based on optimization model,which can ensuring PAPR performance at the same time,reduce the error rate.In order to achieve better PAPR inhibitory effect,considering the root cause of PAPR,we further proposed that organic combine the improved optimization model of clipping technology and PTS technology.This combination method both modulate the amplitude and phase of the signal,on the one hand,using PTS suboptimal method to rotating signal phase,obtained the optimal sequence of PAPR,this can reducing the probability of occurrence of low peak value,then the improved clipping method further inhibiting PAPR,the method both ensuring PAPR and BER performance.Through the MATLAB software simulation shows that compared with the amplitude and PTS combined with conventional limiting technology and PTS technology to improve the optimization model limits based on combined algorithm to enhance the system performance and reduce the amount of calculation for suppression of OFDM system of PAPR,is a kind of meaningful and easy realization of the new method...