Optimal Transmission Power in a Nonlinear VLC System

作     者：ZHAO Shuang CAI Sunzeng KANG Kai QIAN Hua 

作者机构：Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SeieneesShanghai 200050China Key Laboratory of Wireless Sensor Network&CommunicationChinese Academy of SciencesShanghai 200335China Shanghai Research Center for Wireless CommunicationsShanghai 201210China Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China 

出 版 物：《ZTE Communications》 (中兴通讯技术（英文版）)

年 卷 期：2016年第14卷第2期

页      面：23-28页

学科分类：08[工学] 0803[工学-光学工程] 

基　　金：supported in part by the National Key Science and Technology“863”Project under Grant No.SS2015AA011303 the Science and Technology Commission Foundation of Shanghai under Gant No.14511100200 

主　　题：nonlinearity light emitting diode （LED） SNDR 

摘      要：In a visible light communication （VLC） system, the light emitting diode （LED） is nonlinear for large signals, which limits the trans- mission power or equivalently the coverage of the VLC system. When the input signal amplitude is large, the nonlinear distortion creates harmonic and intermodulation distortion, which degrades the transmission error vector magnitude （EVM）. To evaluate the impact of nonlinearity on system performance, the signal to noise and distortion ratio （SNDR） is applied, defined as the linear signal power over the thermal noise plus the front end nonlinear distortion. At a given noise level, the optimal system performance can be achieved by maximizing the SNDR, which results in high transmission rate or long transmission range for the VLC system. In this paper, we provide theoretical analysis on the optimization of SNDR with a nonlinear Hammerstein model of LED. Simulation results and lab experiments validate the theoretical analysis.