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.
出处
《中国激光》
EI
CAS
CSCD
北大核心
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)
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
optical communications visible light communications light-emitting diode nonlinear distortion memory effects adaptive predistortion algorithm
