LED记忆非线性自适应预失真技术研究  

Research of Adaptive Predistortion Technique for Nonlinear LEDs with Memory Effects

作　　者：姚赛杰[1,2] 徐浩煜[3] 汪亮友 周婷[1,2] 钱骅[1,2] 

机构地区：[1]中国科学院上海微系统与信息技术研究所,上海200050 [2]中国科学院无线传感网与通信重点实验室,上海200050 [3]中国科学院上海高等研究院,上海201210 [4]同济大学电子与信息工程学院,上海201804

出　　处：《中国激光》2014年第11期148-153,共6页Chinese Journal of Lasers

基　　金：国家自然科学基金重点项目(61231009);上海市科技创新计划(13511503200;13511503202;13511507502)

摘　　要：发光二极管(LED)是可见光通信系统(VLC)中最主要的非线性器件,同时由于通带内非平坦的频率响应还伴随着记忆效应。LED的记忆非线性主要恶化了VLC系统的误差矢量幅度(EVM)和比特误码率(BER)。预失真技术通常被用来补偿LED的非线性,从而提高可见光通信系统的性能。现有的预失真技术都不具备自适应性并且没有考虑到LED的记忆效应。提出了一种新的预失真架构,即在发射端增加一路反馈链路来获得LED的输出信号,同时使用记忆多项式模型来自适应地训练并补偿LED的记忆非线性。仿真结果显示提出的预失真技术的BER性能优于现有的方法。In a visible light communication（VLC）system,the light-emitting diode（LED）is the major source of nonlinearity and exhibits memory effects due to the in-band non-flat frequency response.The LED nonlinearity with memory effects degrades the error vector magnitude（EVM）and bit error rate（BER）in the VLC system.In general,the predistortion technique is mostly utilized to compensate for the LED nonlinearity and thus enhances the performance of the VLC system.However,the existing predistortion techniques cannot work adaptively and neglect the LED memory effects.A new predistortion architecture is proposed by adding a feedback path to obtain the LED output signal and estimating the LED nonlinearity with memory effects by memory polynomial model adaptively.The simulation results show that the proposed technique outperforms the existing methods in terms of BER.

关 键 词：光通信 可见光通信 发光二极管 非线性失真 记忆效应 自适应预失真算法 

分 类 号：TN929.12[电子电信—通信与信息系统]