光电工程, 2012, 39 (8): 80, 网络出版: 2012-09-12
影响分布式光纤传感器后向瑞利散射波形的关键因素研究
Experimental Investigations of Few Key Factors of Affecting Coherent Backscattered Signals of Distributed Optical Fiber Sensor
分布式光纤传感 后向瑞利散射 消光比 传感长度 菲涅耳反射 distributed optical fiber sensor Rayleigh backscattering extinction ratio sensing length Fresnel reflection
摘要
基于相干后向瑞利散射原理搭建了一套分布式光纤传感系统, 并设计了一种优化的掺铒光纤放大器。以此为基础进行实验, 分析了消光比、传感距离和传感光纤前后端反射等几个关键因素对相干后向瑞利散射波形的影响。实验结果表明:适当地设计电光调制器偏置电压与掺铒光纤放大器, 可明显改善注入脉冲信号峰值功率和消光比;由于注入信号光消光比的限制, 短距离传感比长距离传感更容易获得优良的散射信号;消除传感光纤前后端的菲涅耳反射也能显著提升散射信号的质量与稳定性。
Abstract
A distributed optical fiber sensor system based on coherent Rayleigh backscattered theory is set up, and an optimized Erbium-doped fiber amplifier (EDFA) is designed. The influence of few key factors such as extinction ratio, sensing distance and reflections from the sensing fiber on backscattered profile are analyzed. Experiments show that: the peak power and extinction ratio of injection pulse can be obviously improved through properly adjusting the offset voltages of Electro-Optic Modulator and EDFA. Because of the limit of extinction ratio of pulse, the short distance sensing is easier to obtain good scattered waveforms than long distance sensing. Eliminating the Fresnel reflections from the front-end and back-end of the sensing fiber can also improve the quality and stability of the scattering signals.
张晓磊, 陈学义, 严冰, 陈雪军, 涂郭结, 梁云仙, 倪志波, Brian Culshaw, 董凤忠. 影响分布式光纤传感器后向瑞利散射波形的关键因素研究[J]. 光电工程, 2012, 39(8): 80. ZHANG Xiao-lei, CHEN Xue-yi, YAN Bing, CHEN Xue-jun, TU Guo-jie, LIANG Yun-xian, NI Zhi-bo, Brian Culshaw, DONG Feng-zhong. Experimental Investigations of Few Key Factors of Affecting Coherent Backscattered Signals of Distributed Optical Fiber Sensor[J]. Opto-Electronic Engineering, 2012, 39(8): 80.