中国激光, 2010, 37 (4): 1037, 网络出版: 2010-04-20
基于布里渊时域分析的分布式光纤传感入侵定位系统
A Brillouin Optical Time Domain Analysis Based Distributed Fiber Optic Intrusion Sensor System
光纤光学 分布式光纤传感 布里渊时域分析 入侵检测 应变检测 fiber optics distributed fiber optic sensor Brillouin optical time domain analysis intrusion detection strain detection
摘要
基于布里渊时域分析(BOTDA)对温度和应变的检测原理,构建了分布式光纤传感入侵定位系统。该系统只检测应变事件位置,不检测温度和应变绝对值,因此简化了BOTDA技术中复杂的频率检测方法。系统以脉冲光作为抽运光,反方向传输的连续光作为探测光。分析表明该入侵定位系统在抽运光产生的布里渊峰值频率小于连续光的频率时具有较高的灵敏度,存在一最佳频率偏移使探测灵敏度最高。当传感光纤所处温度改变时,可以通过调节抽运光频率使系统始终保持最佳的灵敏度。
Abstract
A distributed fiber optic intrusion sensor system based on Brillouin optical time domain analysis (BOTDA) is proposed. The absolute values of temperature and strain are not required in this system. So the complicated frequency analyzer is omitted,which simplifies the BOTDA system. An optical pulsed signal is used as pump and a continuous wave optical signal in counter propagating direction is used as the detected light. It is concluded that the best sensitivity can be achieved when the frequency of continuous wave is higher than the Brillouin peak gain frequency produced by pump and there exists an optimal frequency offset that makes the highest sensitivity. When the temperature of the optical fiber changes,the optimal sensitivity can be achieved by adjusting the pump frequency.
洪小斌, 郭宏翔, 伍剑. 基于布里渊时域分析的分布式光纤传感入侵定位系统[J]. 中国激光, 2010, 37(4): 1037. Hong Xiaobin, Guo Hongxiang, Wu Jian. A Brillouin Optical Time Domain Analysis Based Distributed Fiber Optic Intrusion Sensor System[J]. Chinese Journal of Lasers, 2010, 37(4): 1037.