Research And Simulation Of Peak-to-average Power Ratio Reduction Technology For Index-modulated OFDM Systems

With the large-scale promotion of 4G technology,5G technology has not yet had a unified standard.The major colleges and universities,research institutions,and so on put their effort on the new technology.Compared to the traditional OFDM system,the index modulation(IM)system has become one of the hot research topics in recent years,with anti inter-carrier interference(anti-ICI)and better energy efficiency,lower bit error rate(BER)when interleaved,more flexible configuration advantages.Therefore,it has drawn widespread attention from related international teams.The research of this paper is based on the traditional PAPR(Peak to Average Power Ratio)distribution,The PAPR distribution of the indexed OFDM system is analyzed,and the PAPR performance of the OFDM system is discussed according to the characteristics of the index modulation OFDM.The PAPR suppression algorithm existing in the traditional OFDM is extended to the index modulation OFDM,and the PAPR suppression performance is compared with each other.In contrast to the shortcomings of the algorithm,an improved algorithm based on indexed OFDM is proposed.Finally,the application of partial transmission sequence method(PTS)in index modulation OFDM is analyzed,and an improved PTS sub-information placement method is proposed.The first chapter reviews the development and research status of OFDM system and OFDM-IM system.The second chapter introduces the structure of OFDM-IM system,and deduces and analyzes its PAPR performance.The PAPR performance comparison between the OFDM-IM system and the traditional OFDM system is given.Secondly,the influence of different pilot sequences,pilot quantity and pilot energy on PAPR performance of indexed OFDM systems is discussed.A low PAPR pilot aided index modulation OFDM system is proposed.In chapter 2,we analyze the PAPR problem of OFDM-IM system,evaluate the PAPR suppression performance of common iterative clipping filter algorithm and subcarrier reservation algorithm in OFDM-IM system,and give the analysis results.Aiming at the shortcomings of the above conclusions,a new improved algorithm and simulation analysis are proposed in the OFDM-IM system.After the introduction of the predistortion algorithm in Chapter 3,the fourth chapter introduces the application of the no-distortion PTS algorithm in the index modulation OFDM system,and analyzes the influence of different grouping methods,alternative sequence selection and sub-information transmission on PAPR performance.The improvement of the BER effect is provided for the transmission of the sub-information(SI)The results of this paper show that the index-modulated OFDM system can achieve greater PAPR suppression with less computational complexity than traditional OFDM systems and is superior to BER performance than traditional OFDM systems.The improvement of PTS algorithm sub-information transmission greatly reduces the degradation of bit error rate due to the error of sub-information transmission.