基于BOTDR散射谱的应变提取方法研究  

Research on the strain extraction method based on BOTDR scattering spectrum

作　　者：陈刚[1] 段洁[1] 衣文索[1] 巩楠楠 林家楷 Chen Gang;Duan Jie;Yi Wensuo;Gong Nannan;Lin Jiakai(School of Opto-electronic Engineering,Changchun University of Science and Technology,Changchun 130012,China)

机构地区：[1]长春理工大学光电工程学院,长春130012

出　　处：《仪器仪表学报》2021年第1期75-81,共7页Chinese Journal of Scientific Instrument

基　　金：吉林省科技计划发展项目(20150520094JH)资助。

摘　　要：针对布里渊后向散射原理的应变传感系统信号检测方法进行研究,目前该领域信号检测方法普遍存在计算量大,精度不高,耗时大等诸多问题,提出了一种自适应梯度下降算法(Adam算法)对布里渊散射信号进行拟合计算,同时搭建了外差相干检测的布里渊应变测量系统。实验结果表明,用Adam算法拟合散射谱曲线后解调的平均应变误差为24.89με,是高斯-牛顿算法拟合曲线最大应变误差的51.96%,是列文伯格-马夸尔特算法拟合曲线最大应变误差的57.42%;Adam算法拟合散射谱曲线的拟合度佳(0.998 9),均方根误差小(0.110 5)拟合测量的精密度高,而且信号处理时间仅为18.5 ms。研究结果对布里渊散射传感技术高精度数据特征提取提供了理论和实验依据。The signal detection method of stress-strain sensing system based on the principle of Brillouin backscattering is studied. At present, the signal detection method in this field generally has many problems, such as large amount of calculation, low accuracy, and poor consistency. This paper proposes an adaptive gradient descent algorithm(Adam algorithm), which can be used to fit the Brillouin scattering signal. Meanwhile, a Brillouin strain measurement system for heterodyne coherent detection is established. Experimental results show that the average strain error demodulated after fitting the scattering spectrum curve with the Adam algorithm is 24.89 με, which is 51.96% of the maximum strain error of the Gauss-Newton algorithm fitting curve. This value is Levenberg-Marquardt LM algorithm fits 57.42% of the maximum strain error of the curve. When Adam algorithm is used to fit the scattering spectrum curve, the good fit is 0.998 9 and small root mean square error is 0.110 5. These results indicate high precision of fitting measurement and signal processing. In addition, the signal processing time is only 18.5 ms. Research results of this study provide theoretical and experimental basis for the high-precision data feature extraction of Brillouin scattering sensing technology.

关 键 词：分布式光纤传感 布里渊散射 布里渊光时域反射系统 应变检测 曲线拟合 

分 类 号：TH741[机械工程—光学工程] TN247[机械工程—仪器科学与技术]