Author Affiliations
Abstract
School of Computer and Communication Engineering, University of Science and Technology Beijing, Beijing 100083, China
The phase-sensitive time-domain reflectometer () has been popularly used for events detection over a long period of time. In this study, the events classification methods based on convolutional neural networks (CNNs) with different features, i.e., the temporal-spatial features and time-frequency features, are compared and analyzed comprehensively in . The developed CNNs aim at distinguishing three typical events: wind blowing, knocking, and background noise. The classification accuracy based on temporal-spatial images is higher than that based on time-frequency images (99.49% versus 98.23%). The work here sets a meaningful reference for feature extraction and application in the pattern recognition of .
phase-sensitive time-domain reflectometer convolutional neural network temporal-spatial images time-frequency images Chinese Optics Letters
2023, 21(4): 040601
1 上海大学特种光纤与光接入网省部共建重点实验室培育基地, 上海 200444
2 中国科学院上海光学精密机械研究所空间激光信息传输与探测技术重点实验室, 上海 201800
3 中国科学院大学材料与光电研究中心, 北京 100049
提出一种新型的基于内调制啁啾脉冲的高信噪比(SNR)直接探测型相位敏感光时域反射计(φ-OTDR)。通过理论分析可得,利用啁啾脉冲的方法并通过提高受激布里渊阈值可提高注入光能量,提高探测信号中的直流分量可使信号与噪声分离,进而提升SNR。提出一种φ-OTDR系统信噪比的综合评判方法,对SNR的统计特性进行分析。同时,开展了基于分布式反馈激光器的内调制直接探测型φ-OTDR系统实验研究,利用可调谐滤波器对内调制产生的频率啁啾范围进行控制,经对比实验验证,可得所提系统与传统φ-OTDR系统的信噪比期望相当,分布方差更小,测量可靠度更高的结论。此外,该系统还具有成本低、结构简单等优点,实际应用时可以利用光纤布拉格光栅代替可调谐滤波器,提升其应用的灵活性,为工程应用提供新的解决方案。
光通信 相位敏感光时域反射计 内调制 啁啾脉冲 信噪比 低成本
