摘要
相干光时域反射仪(COTDR)测量曲线的振幅变化受相干瑞利噪声影响较大,严重时导致系统发生误报并降低系统性能。主要探索了系统中相干瑞利噪声的产生机理及其影响因素,给出了各个因素与瑞利散射系数之间的定量关系,并仿真分析了光纤折射率、系统空间分辨率和光源频率的变化对干涉衰落波形的具体影响;从改变光源频率的角度总结分析了近年来降低COTDR系统中干涉衰落的主要方法及其局限性,并对COTDR系统在长距离光通信链路和地铁隧道监测等方面的应用进行了介绍。
The amplitude variation of the coherent optical time domain reflectometer(COTDR)measurement curve is greatly affected by coherent Rayleigh noise,which leads to system false alarms and system performance degradation.The paper describes the mechanism and influencing factors of coherent Rayleigh noise in COTDR system,the quantitative relationship between each factor and the Rayleigh scattering coefficient is given,and simulates the impact of the fiber refractive index,spatial resolution and the frequency variation of laser source on the interference fading waveform in detail.Finally it summarizes the main methods and limitations of reducing the interference fading in view of changing the laser frequency in COTDR system.Several important applications of COTDR are given,including the monitoring of ultra long communication optical fiber link and the subway tunnel.
作者
孟令刚
李永倩
张立欣
MENG Linggang;LI Yongqian;ZHANG Lixin(Department of Electronic and Communication Engineering,North China Electric Power University,Baoding Hebei 071003,China)
出处
《光通信技术》
北大核心
2019年第12期45-49,共5页
Optical Communication Technology
基金
国家自然科学基金资助项目（61775057、61377088）资助
中央高校基本科研业务费专项资金（2019MS086）资助
关键词
相干光时域反射系统
相干瑞利噪声
传感光纤
coherent optical time domain reflectometer system
coherent Rayleigh noise
sensor fiber
