一种克服色度色散影响的四倍频光毫米波信号产生方法  

Generation of Frequency Quadruple Optical Millimeter-Wave Signal to Overcome Chromatic Dispersion

作　　者：朱子行[1] 赵尚弘[1] 幺周石 谭庆贵 李勇军[1] 楚兴春[1] 赵顾颢[1] 王翔[1] 

机构地区：[1]空军工程大学电讯工程学院,陕西西安710077 [2]空间微波技术国防科技重点实验室,陕西西安710000

出　　处：《中国激光》2012年第4期99-105,共7页Chinese Journal of Lasers

基　　金：国家863计划(2007AA01Z294)资助课题

摘　　要：提出一种克服色度色散影响的四倍频光毫米波信号产生方法。该方法使用一个双驱动马赫-曾德尔调制器,通过调整上、下两路射频信号的相位差、直流偏置点、调制系数以及基带信号增益,将数据信号仅调制到四倍频光毫米波信号的一个2阶边带上传输,解决了色度色散引起的码元走离问题,有效增加了传输距离。理论分析和仿真实验结果表明,信号在光纤中传输120km后眼图仍然十分清晰,经过60km传输后的功率代价约为0.45dB。另外,基于频率再用技术,没有调制数据的另一个2阶边带信号还可以作为全双工光纤无线通信(RoF)系统的上行链路光载波,简化了基站配置。仿真实验结果表明,双向2.5Gbit/s数据信号在光纤中传输40km后,功率代价小于0.6dB。A scheme for generation of frequency quadruple optical millimeter-wave signal to overcome chromatic dispersion is proposed.With radio frequency signal phase,bias,modulation index,and base-band signal gain adjustment,a dual-drive Mach-Zehnder modulator is used to generate frequency quadruple optical millimeter-wave signal only carried by one second-order sideband which solves the problem of time shift of code caused by chromatic dispersion,so the transmission distance is extended greatly.Theoretical analysis and simulation results show that the eye diagram keeps open and clear even when the optical millimeter-wave signals are transmitted over 120 km and the power penalty is about 0.45 dB after fiber transmission distance of 60 km.Furthermore,due to one pure optical component carrying no signals,a full duplex radio-over-fiber（RoF） link based on frequency reuse is also built to simplify the base station.The bidirectional 2.5 Gbit/s data is successfully transmitted over 40 km standard single mode fiber with less than 0.6 dB power penalty in the simulation.

关 键 词：光通信 光纤无线通信系统 光生毫米波信号 色度色散 四倍频 马赫-曾德尔调制器 

分 类 号：TN929.11[电子电信—通信与信息系统]