一种局部受激布里渊光时域反射系统最优探测距离自动识别方法  

Optimal Detection Distance Automatic Identification Method for Local Stimulated Brillouin Optical Time Domain Reflectometry System

作　　者：陈奕 高波 付林林 王笑微 朱海军 刘江涛 钟振涛 李拥政 郭林峰 徐小敏 CHEN Yi;GAO Bo;FU Linlin;WANG Xiaowei;ZHU Haijun;LIU Jiangtao;ZHONG Zhentao;LI Yongzheng;GUO Linfeng;XU Xiaomin(School of Physics and Optoelectronic Engineering,Nanjing University of Information Science&Technology,Nanjing 210044,China;Nanjing Metro Construction Co.,Ltd,Nanjing 210019,China;China Railway Tunnel Group No.2 Co.,Ltd,Langfang 065200,China;China Railway(Shanghai)Investment Group Co.,Ltd,Shanghai 200126,China;China Railway No.3 Group East China Construction Co.,Ltd,Nanjing 211153,China;Jiangsu Key Laboratory for Optoelectronic Detection of Atmosphere and Ocean,Nanjing 210044,China;Jiangsu International Joint Laboratory on Meterological Photonics and Optoelectronic Detection,Nanjing 210044,China;Department of Engineering,University of Cambridge,Cambridge,CB21PZ,United Kingdom)

机构地区：[1]南京信息工程大学物理与光电工程学院,南京210044 [2]南京地铁建设有限责任公司,南京210019 [3]中铁隧道集团二处有限公司,廊坊065200 [4]中铁(上海)投资集团有限公司,上海200126 [5]中铁三局集团华东建设有限公司,南京211153 [6]江苏省大气海洋光电探测重点实验室,南京210044 [7]江苏省气象光子学与光电探测国际合作联合实验室,南京210044 [8]剑桥大学工程系,英国剑桥CB21PZ

出　　处：《光子学报》2025年第3期43-56,共14页Acta Photonica Sinica

基　　金：国家自然科学基金(No.62175113);江苏省重点研发计划(No.BE2022076)。

摘　　要：工程使用中的分布式传感光缆的长度、种类和状态,以及布里渊光时域反射系统中光源器件的线宽、功率等参数都会影响受激布里渊散射阈值的大小,如何在各种不同的状态对应的受激阈值条件下,最大程度发挥系统检测性能,是紧凑型中低成本布里渊光时域反射系统在工程应用中值得研究的问题。提出一种基于短时傅里叶变换的自动识别光纤沿线受激布里渊散射的光电路解调方案以及信号处理方法,以确定局部受激布里渊光时域反射系统最优传感距离。在实验中,对2000 m的光纤进行测量,设置脉冲宽度为20 ns,使用20 kHz的脉冲频率,识别到受激布里渊散射位置为1230.2 m,并通过布里渊频移实验数据验证了该方法的有效性。此外,还对不同脉冲宽度、频率和光纤长度进行了实验。通过实验研究进一步明确了紧凑型低成本局部受激布里渊光时域反射系统中传感光纤的有效受激区域和最佳传感使用距离,增强了布里渊光时域反射系统的工程实用性。With the continuous development of distributed optical fiber sensing technology,the Brillouin Optical Time Domain Reflectometry(BOTDR)system,due to its single-ended monitoring characteristics,electromagnetic interference immunity,and real-time sensing capabilities for temperature/strain changes,has become increasingly applied in structural health monitoring fields,particularly in large infrastructures such as bridges,dams,and subway tunnels.However,the weak spontaneous Brillouin scattering limits the performance of the BOTDR system.Increasing the input optical pulse energy enhances the scattering effect;however,if the energy exceeds a certain threshold,stimulated Brillouin scattering can deplete the pulse energy rapidly,reducing the sensing distance and impacting the system's performance.Factors such as the length,type,and condition of the distributed sensing fiber,as well as the linewidth and power of the light source in the BOTDR system,affect the stimulated Brillouin scattering threshold.Therefore,how to optimize the system's detection performance under varying stimulated threshold conditions is a key issue for compact and cost-effective BOTDR systems in practical engineering applications.This paper presents an automated detection method for identifying stimulated Brillouin scattering in optical fibers.The technique leverages Short-Time Fourier Transform(STFT)-based optoelectronic demodulation and advanced signal processing.Its primary goal is to optimize the sensing distance for localized Stimulated Brillouin Optical Time-Domain Reflectometry(BOTDR)systems.The method uses an optoelectronic demodulation device to collect the raw time-domain Brillouin scattering signal along the fiber to be tested,applying STFT processing to obtain the Brillouin Gain Spectrum(BGS).By analyzing the peak intensity distribution of the BGS,a Brillouin peak intensity map along the fiber is plotted.A moving average method is used to remove random noise,followed by polynomial fitting to obtain the first-and second-order derivative cur

关 键 词：分布式光纤传感 布里渊光时域反射 短时傅里叶变换 自发布里渊散射 受激布里渊反射 

分 类 号：O437.2[机械工程—光学工程]