降低DCO-OFDM可见光系统峰均比的SLM改进算法  

An Improved SLM Algorithm for Reducing PAPR of DCO-OFDM Visible Light Communication System

作　　者：燕慧英[1] 夏玉杰[1] 高雅[1] YAN Huiying;XIA Yujie;GAO Ya(College of Physics and Electronic Information,Luoyang Normal University,Luoyang 471934,China)

机构地区：[1]洛阳师范学院物理与电子信息学院,河南洛阳471934

出　　处：《东莞理工学院学报》2020年第3期25-28,40,共5页Journal of Dongguan University of Technology

基　　金：河南省高等学校重点科研项目(17A510013)。

摘　　要：由于直流偏置光正交频分复用(DCO-OFDM)系统具有较高的峰均比(PAPR),严重影响了系统的传输性能,采用传统的选择性映射(SLM)算法虽然可以降低DCO-OFDM可见光系统的峰均比,但降低的幅度有限,同时需要传输较多的边带信息。为此,可以对传统的SLM算法进行适当改进,使用混沌序列作为相位旋转因子,减少边带信息的传输量;然后对SLM算法选出的PAPR最小的一组信号进行离散余弦变换(DCT),通过减小时域信号之间的相关性达到进一步降低峰均比的目的。仿真结果表明,SLM的改进算法不仅明显降低了系统的峰均比,而且极大减少了边带信息的传输。Due to the high peak-to-average(PAPR)of dc offset optical orthogonal frequency division multiplexing(DCO-OFDM)system,the transmission performance of the system is seriously affected.Although the traditional selective mapping(SLM)algorithm can reduce the peak-to-average of DCO-OFDM visible light system,the reduction range is limited,and more sideband information needs to be transmitted.Therefore,the traditional SLM algorithm can be improved by using chaotic sequence as the phase rotation factor to reduce the amount of sideband information transmission.Then the discrete cosine transformation(DCT)is applied to the smallest set of PAPR signals selected by SLM algorithm to further reduce the peak-to-average by reducing the correlation between the time-domain signals.Simulation results show that the improved SLM algorithm not only significantly reduces the ratio of the system,but also greatly reduces the transmission of sideband information.

关 键 词：峰均比 SLM 混沌序列 DCT 

分 类 号：TN919.3[电子电信—通信与信息系统]