基于希尔伯特-黄变换的双马赫-曾德分布式光纤传感振动定位方法  

A Hilbert-Huang transform method for vibration localization based on a dual Mach-Zehnder distributed optical fiber sensor

作　　者：杨文晨 秦增光[1,2] 刘兆军 徐演平[3] 李钊 渠帅 丛振华 王泽群 YANG Wen-chen;QIN Zeng-guang;LIU Zhao-jun;XU Yan-ping;LI Zhao;QU Shuai;CONG Zhen-hua;WANG Ze-qun(School of Information Science and Engineering,Shandong University,Qingdao 266237,China;Shandong Provincial Key Laboratory of Laser Technology and Application,Qingdao 266237,China;Ministry of Education Key Laboratory of Laser and Infrared System Integration Technology,Shandong University,Qingdao 266237,China)

机构地区：[1]山东大学信息科学与工程学院,山东青岛266237 [2]山东省激光技术与应用重点实验室,山东青岛266237 [3]山东大学激光与红外系统集成技术教育部重点实验室,山东青岛266237

出　　处：《中国光学》2021年第6期1410-1416,共7页Chinese Optics

基　　金：山东省自然科学基金(No.ZR2020MF110,No.ZR2020MF118)。

摘　　要：双马赫-曾德(M-Z)干涉仪系统因其光路简单、灵敏度高、频率响应宽等独特优势受到了广泛的关注及应用,但由于其非常容易受到外界环境噪声的影响,直接采取互相关计算方法获取扰动信号位置会导致较大的测量误差。本文提出了一种基于希尔伯特-黄变换(HHT)的数据信号处理方案用于实现高精度的分布式光纤振动定位检测。通过对接收到的两路光信号进行经验模态分解得到本征模函数,并对所有本征模函数进行希尔伯特变换叠加得到希尔伯特谱,从而可以清晰直观地提取到由振动信号引起的高相似度光信号信息,再通过互相关计算由振动信号引起的时间延迟,从而准确计算振动位置信息。相比于传统的直接互相关计算方法,本方法可以有效识别及提取双M-Z干涉仪系统中振动信号引起的特征信息,从而可以有效降低外界环境噪声对系统的影响,减小定位误差。本文对所提出的方法进行了相关理论分析,并搭建了双M-Z干涉仪系统进行相关实验验证。实验结果表明,与传统直接互相关方法相比,本方法可以有效减少互相关数据的计算量,同时该方法可以有效提高振动位置的定位精度,在2 km的传感光纤长度、10 MHz采样率下,定位精度可达10 m。本文提出的基于双马赫-曾德干涉仪系统的分布式光纤传感技术具有较高的实际应用价值。The dual Mach-Zehnder interferometer system has received extensive attention and applications due to its unique advantages such as simple optical path,high sensitivity and wide frequency response.However,it is very susceptible to external environmental noise and direct cross-correlation calculation meth-od will lead to a large error.This paper proposes a data signal processing scheme based on Hilbert-Huang Transform(HHT)to realize high-precision distributed optical fiber vibration position detection.In this meth-od,the eigenmode function is obtained by the empirical mode decomposition of the two received optical sig-nals.The Hilbert transform and superposition of all eigenmode functions are performed to obtain the Hilbert spectrum,which can be clearly and intuitively extracted.It can accurately calculate the vibration position in-formation by calculating the time delay caused by the vibration signal through cross-correlation.Compared with the traditional direct cross-correlation calculations,this method can effectively identify and extract the characteristic information caused by the vibration signal in the dual M-Z system.Thereby it can effectively reduce the impact of external environmental noise on the system and reduce the positioning error.This paper analyzes the related theory of the proposed method and builds a dual M-Z system for related experimental verification.The experimental results show that,compared with the traditional direct cross-correlation meth-od,this method can effectively reduce the amount of calculation of cross-correlation data.At the same time,it can effectively improve the positioning accuracy of the vibration position.Under 10 MHz sampling rate,the positioning accuracy can reach 10 m.Therefore,the distributed optical fiber sensing technology based on the dual Mach-Zehnder interferometer system proposed in this paper has high application value.

关 键 词：光纤传感 希尔伯特-黄变换 双马赫-曾德干涉仪 定位方法 端点检测 

分 类 号：TP212.1[自动化与计算机技术—检测技术与自动化装置]