基于相位敏感光时域反射计的语音与脚步振动信号监测系统研究  

Voice and Footstep Signal Monitoring System Based on Phase Sensitive Optical Time Domain Reflectometer

作　　者：孙文达 郑晶[1] 孙远 Sun Wenda;Zheng Jing;Sun Yuan(College of Geoscience and Surveying Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)地球科学与测绘工程学院,北京100083

出　　处：《激光与光电子学进展》2023年第23期101-107,共7页Laser & Optoelectronics Progress

基　　金：国家重点研发计划(2021YFC3090302);中央高校基本科研业务费(2021JCCXDC02)。

摘　　要：基于分布式光纤传感技术在周界安防领域广阔的应用前景,对振动信号在单模光纤上的调制机理和解调原理进行了详细的推导和分析,构建了一套基于相位敏感光时域反射计的分布式声波传感器(DAS)系统,设计了完整的压电陶瓷振动信号检测实验和语音与脚步信号检测实验,通过移动差分求和与正交解调算法实现振动信号的强度解调和相位解调。在语音检测实验中采用铁质半封闭空心圆柱体提高了光纤对声波的灵敏度,对原始语音和复现语音做了平均主观意见值调研来验证语音信号的质量,在时域和频域对DAS系统采集的脚步信号进行了分析和解释,同时将单个脚步信号的相关特征进行提取说明。实验证明,本系统能在传输距离为2 km时实现复杂的语音和脚步信号检测,空间分辨率可达2.2 m,能较好地用于周界安防中的语音与脚步监测。Based on the broad application prospect of distributed optical fiber sensing technology in the field of perimeter security,the modulation mechanism and demodulation principle of vibration signals on single-mode optical fiber are deduced and analyzed in detail,and a set of distributed acoustic sensor(DAS)system based on phase sensitive time domain reflectometer is constructed.A complete piezoelectric ceramic vibration signal detection experiment and voice and footstep signal detection experiment are designed.The intensity and phase demodulation of vibration signals are realized by moving difference summation and orthogonal demodulation algorithm.In the voice detection experiment,the sensitivity of optical fiber to sound waves is improved by using an iron semi-closed hollow cylinder.The subjective mean opinion value survey of the original voice and the repeated voice is made to verify the quality of the speech signal.The footstep signals collected by DAS system are analyzed and interpreted in the time domain and frequency domain,and the relevant features of the single-step signal is extracted and explained.The experiments prove that this system can realize complex voice and footstep signal detection in the transmission distance of 2 km,and the spatial resolution can reach 2.2 m,which can be well applied to voice and footstep monitoring in the perimeter security.

关 键 词：分布式光纤传感 Φ-OTDR 正交解调 平均主观意见值 周界安防 

分 类 号：TN29[电子电信—物理电子学]