光学技术, 2017, 43 (5): 473, 网络出版: 2017-11-07
Φ-OTDR光纤预警系统的周界安防入侵定位
Φ-OTDR optical fiber pre-warning system for perimeter security intrusion location
光纤分布式传感 周界防护 小波去噪 入侵定位 fiber distributed sensing Φ-OTDR Φ-OTDR perimeter protection wavelet-denoising intrusion location
摘要
由于相位敏感光时域反射仪(Φ-OTDR, Phase-sensitive Optical Time Domain Reflectometer)光纤预警系统高灵敏度的特性, 使其对于环境中的声波及瞬时高频噪声也异常敏感, 如何提高信噪比, 使有用信号在众多噪声中显现出来, 实现精确定位, 成为该领域研究的关键问题。分析了Φ-OTDR分布式光纤系统的工作原理, 介绍了分离平均与差分、滑动平均与差分以及小波阈值去噪三种常用的定位算法。利用连续小波变换分析了挖掘信号的功率谱分布随距离传播的变化规律, 并提出了一种利用小波高频分量进行定位的算法方案。实验证明小波高频分量定位算法具有更高的定位精度, 信噪比为9.6033dB。
Abstract
Since Phase-sensitive Optical Time Domain Reflectometer (Φ-OTDR) fiber optic warning system is extremely sensitive to the environment, how to improve the signal noise ratio and make useful signal apparent among the noise has become the key area of research. The working principle of Φ-OTDR distributed fiber optic system is analyzed. Three commonly used algorithms are introduced with separating averaging and difference method, moving averaging and difference method and wavelet threshold de-noising method. A localization algorithm is proposed based on wavelet high frequency component by analyzing digging signal's variation with distance. This localization algorithm can highly improve the sensitivity of the system and realize the noise ratio as 9.6033dB.
董百合, 江飞, 邢冀川. Φ-OTDR光纤预警系统的周界安防入侵定位[J]. 光学技术, 2017, 43(5): 473. DONG Baihe, XING Jichuan, JIANG Fei. Φ-OTDR optical fiber pre-warning system for perimeter security intrusion location[J]. Optical Technique, 2017, 43(5): 473.