降FBMC系统峰均比的改进DFT扩频技术  

Improved DFT spreading for the PAPR reduction of the FBMC system

作　　者：刘松[1] 李玥 刘鹏[1] Liu Song;Li Yue;Liu Peng(School of Electrical and Electronic Engineering,North China Electric Power University,Beijing 102206,China)

机构地区：[1]华北电力大学电气与电子工程学院

出　　处：《电子技术应用》2019年第10期76-79,共4页Application of Electronic Technique

摘　　要：滤波器组多载波(Filter Bank Multi-Carrier,FBMC)是5G移动通信系统中可能替代OFDM的调制方式,但是其峰均比(Peak to Average Power Ratio,PAPR)较高。DFT扩频技术利用DFT扩展输入信号,将FBMC信号的PAPR降到单载波传输的水平,但是仍存在缺点:经过推导发现,在同一符号周期内,传输符号x(t)中有4种不同的符号,导致PAPR值较高。因此,对DFT扩频技术中的相移项进行改进,提出了一种基于多载波等时移条件的DFT扩频(Identically Time Shifted Multicarrier-DFT spreading,ITSM-DFTs)算法。该算法充分利用了DFT扩频技术的单载波效应,理论分析和仿真结果表明,该算法有效降低了FBMC系统的PAPR。Filter Bank Multi-Carrier(FBMC) is a modulation scheme that may replace OFDM in 5G mobile communications, but its peak to average power ratio(PAPR) is higher. The DFT-spreading technique is to spread the input signal with DFT, which can reduce the PAPR of FBMC signal to the level of single carrier transmission. But there are still shortcomings : after derivation, the PAPR is substantially high due to the four different symbols added at the symbol timings in the transmit waveform x(t). For this shortcoming,this paper improves the phase shift terms and proposes an identically time shifted multicarrier-DFT spreading(ITSM-DFTs) algorithm,which fully exploits the single carrier effect of DFT-spreading. Theoretical analysis and simulation results show that the algorithm effectively reduces the PAPR of the FBMC system.

关 键 词：滤波器组多载波 峰均比 DFT扩频技术 相移项 

分 类 号：TN929.5[电子电信—通信与信息系统]