基于超结构光纤光栅的自发布里渊散射检测系统设计与实现  

Designing & realization of spontaneous Brillouin scattering detecting system based on super-structure fiber bragg grating

作　　者：张永智[1] 王荣[1] 徐智勇[1] 

机构地区：[1]解放军理工大学通信工程学院,江苏南京210007

出　　处：《解放军理工大学学报（自然科学版）》2010年第3期239-242,共4页Journal of PLA University of Science and Technology(Natural Science Edition)

基　　金：江苏省自然科学基金资助项目(BK2007501)

摘　　要：为解决光纤背向散射信号中自发布里渊散射信号提取困难的问题,针对自发布里渊散射信号的频谱特点,设计并制作了一种双峰、波长可调结构的超结构光纤光栅滤波器。该滤波器具有滤波抑制比高、滚降特性好、线宽窄、中心波长可调、插损低、稳定性高等特点。通过两级超结构光纤光栅的级联,对瑞利散射信号的抑制达到约30 dB,可以把自发布里渊散射信号的2个峰同时提取出来。在此基础上,搭建了基于布里渊散射技术的全分布式光纤传感实验系统,对长度约为32 km的传感光纤进行了实验测量,在对被测光纤上长度为130、150 m的两段光纤分别施加1200μ,ε温度变化20°C时,系统较清楚地显示出应力、温度对被测光纤的作用效果。测量结果表明,该系统可以实现光纤温度及应力的变化监测。To solve the problems in extracting spontaneous Brillouin scattering signals from backscattering signals in fiber,based on the spectrum characteristics spontaneous Brillouin scattering signals,a double-peak wavelength-variable super-structure FBG filter was designed and made.The filter was featured with high suppression ratio,excellent roll-off,narrow line-width,tunable center wavelength,low insertion loss and stability.Through the 2-level super-structure FBG cascade,inhibition of the Rayleigh scattering signal reached 30 dB,and the double peaks of the spontaneous Brillouin scattering signals could be obtained at the same time.On such basis,the all-distributed optical fiber sensing experimental system based on Brillouin scattering technique was initiated to conduct measurements on the sensing optical fiber of 32 km long.Applied 1200 με,when the temperature changes reached 20°C on the two sections of the tested fiber whose length were 130 m and 150 m respectively,the system distinctly showed the effects on the tested fiber pieces by the strain and the temperature.The testing result proves that the system can be used to monitor the variation in optical fiber temperatures and strains.

关 键 词：自发布里渊散射 超结构光纤光栅 应力 温度 

分 类 号：TP212.14[自动化与计算机技术—检测技术与自动化装置]