光纤分布式声传感的动态范围扩展方法研究  

Research on Dynamic Range Expansion Method of Fiber-Optic Distributed Acoustic Sensing

作　　者：马喆 王逸璇 江俊峰 王双 张建德 杨宁 徐天华 丁振扬 刘铁根 Ma Zhe;Wang Yixuan;Jiang Junfeng;Wang Shuang;Zhang Jiande;Yang Ning;Xu Tianhua;Ding Zhenyang;Liu Tiegen(Tianjin Optical Fiber Sensing Engineering Center,Institute of Optical Fiber Sensing of Tianjin University,Key Laboratory of Opto-Electronics Information Technology,Ministry of Education,School of Precision Instrument and Opto-Electronics Engineering,Tianjin University,Tianjin 300072,China;Key Laboratory of Advanced Transducers and Intelligent Control System,Ministry of Education and Shanxi Province,College of Physics and Optoelectronics,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China;Shandong Institute of Aerospace Electronic Technology,Yantai,Shandong 264000,China)

机构地区：[1]天津大学精密仪器与光电子工程学院光电信息技术教育部重点实验室,天津大学光纤传感研究所天津市光纤传感工程中心,天津300072 [2]太原理工大学物理与光电工程学院新型传感器与智能控制教育部与山西省重点实验室,山西太原030024 [3]山东航天电子技术研究所,山东烟台264000

出　　处：《光学学报》2021年第13期64-71,共8页Acta Optica Sinica

基　　金：国家自然科学基金(61735011,61675152);科技部重大科学仪器开发专项(2013YQ030915);载人四期预研项目;天津市高层次创新创业团队人才发展特支计划;天津131创新人才第一层次培养计划。

摘　　要：提出一种基于线性调频(LFM)脉冲边带调制的光纤分布式传感动态应变范围扩展方法,基于调频带宽与相干时域信号包络平移量之间的反比特性,通过在单脉冲内产生具备不同调频带宽的多调制边带进行传感,对各边带的相干时域信号进行数字带通滤波和分解,以实现对不同动态应变范围事件的同时测量。实验中分别使用调频带宽为40 MHz和200 MHz的LFM信号对边带进行调制,结果表明系统可以同时测量最大幅值为7 nε和350 nε的正弦动态应变事件,这为光纤分布式声传感系统提供一种动态范围拓展方案。A method is proposed to extend the dynamic strain range of fiber-optic distributed sensing based on linear frequency modulation(LFM) pulse sideband modulation. Based on inverse ratio between the frequency-modulated bandwidth and the coherent time-domain signal envelope shift, multiple modulated sidebands with different frequency-modulated bandwidths are generated in a single pulse for sensing. Coherent time-domain signals of each sideband are digitally band-pass filtered and decomposed to achieve simultaneous measurements of events with different dynamic strain ranges. LFM signals with frequency modulated bandwidths of 40 MHz and 200 MHz are used to modulate sidebands in experiments, respectively. The results show that the system can simultaneously measure the maximum amplitude of 7 nε and 350 nε sinusoidal dynamic strain events, which provides a dynamic range expansion scheme for fiber-optic distributed acoustic sensor system.

关 键 词：光纤光学 光纤分布式声传感 线性调频脉冲 边带调制 动态范围 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]