摘要
光频域反射仪(OFDR)是一种光外差探测技术,可用于对大容量光栅阵列的解调,具有测量速度快,空间分辨率高,精度高的优点。但OFDR解调方式中光源的非线性调谐效应会严重影响对光栅阵列的测量精度。本文主要介绍了OFDR的工作原理,从理论上分析了在等光频间隔内,光源扫频速率抖动对拍频信号的影响,进行了仿真实验,分析了实际拍频信号,提出了利用等波纹设计低通滤波器校正主干涉仪和辅助干涉仪拍频信号的方法。实验对20个中心波长为1550.6nm,反射率为0.6%,间隔15cm的光纤光栅阵列进行了位置信息和波长信息的解调。实验结果表明:通过设计的低通滤波器校正非线性抖动信号可以使OFDR解调系统达到良好的解调效果。
Optical frequency domain reflectometer(OFDR)is an optical heterodyne detection technology.It can be used to demodulate fiber optic grating arrays of large capacities.It has the advantages of fast measurement speed,high spatial resolution and high precision.However,the nonlinear tuning effect of the light source in OFDR demodulation mode seriously affects the measurement accuracy of the grating array.This paper mainly introduces the working principles of the OFDR,theoretically analyzes the influence of the light source frequency sweep jittering on the beat frequency signal in the equal optical frequency interval,carries out the simulation and the analysis of the actual beat frequency signal,and proposes the method of utilization of filters to correct the beat frequency of the main interferometer and the auxiliary interferometer.20 fiber Bragg grating arrays with 1550.6 nm central wavelength,0.6%reflectivity and 15 cm interval are demodulated.The results show that the OFDR demodulation system can achieve good demodulation effect with the utilization of the designed low-pass filter correcting the nonlinear jitter signal.
作者
梁晨
梁磊
吴崧
LIANG Chen;LIANG Lei;WU Song(School of Information Engineering,Wuhan University of Technology,Wuhan 430070,China;National Engineering Laboratory for Fiber Optic Sensing Technology,Wuhan University of Technology,Wuhan 430070,China)
出处
《武汉理工大学学报》
CAS
北大核心
2020年第9期83-88,共6页
Journal of Wuhan University of Technology
基金
国家重点研发计划(2018YFF0214700)
广东省中山市科技发展专项(2017F2FC0003)
广东省中山市重大科技专项(2019sdr001)
关键词
光频域反射
波长解调
位置解调
非线性补偿
拍频信号校正
optical frequency domain reflection
wavelength demodulation
position demodulation
non-linear compensation
beat signal correction
作者简介
梁晨(1996-),男,硕士生.E-mail:liangchen@whut.edu.cn
