基于频分复用φ-OTDR的高频振动检测与解调  

High frequency vibration detection and demodulation based on frequency division multiplexing φ-OTDR

作　　者：孙抗[1] 韩毓 何梦阳 SUN Kang;HAN Yu;HE Mengyang(School of Electrical Engineering and Automation,Henan Polytechnic University,Jiaozuo 454000,China)

机构地区：[1]河南理工大学电气工程与自动化学院,河南焦作454000

出　　处：《传感器与微系统》2023年第7期148-151,共4页Transducer and Microsystem Technologies

基　　金：河南省科技攻关项目(202102210092)。

摘　　要：相位敏感光时域反射计(φ-OTDR)是一种借助光纤为传感媒介,检测外部振动信息的可靠方案。为提高系统的探测频率,设计了一种双脉冲频分复用结构的φ-OTDR系统。通过对双脉冲信号中的其中一路采用频分复用技术处理,产生用于检测动态相位变化的不同频率载波信号,使更多的探测脉冲可以同时在光纤中传输。并针对振动信号的解调,提出一种微分自交叉相除的反正切(PGC-DSD-Arctan)算法,解决了传统算法中解调效果受调制深度影响的问题,具有更好的适用性和更高的稳定性。通过搭建系统平台,可以有效地在10 km传感范围内检测并解调出20 kHz振动信号的相位和频率信息。Phase-sensitive optical time-domain reflectometry(φ-OTDR)is a reliable solution for detecting external vibration information by using optical fiber as sensing medium.In order to improve the detection frequency of the system,aφ-OTDR system with double-pulse frequency division multiplexing structure is designed.One way of the dual pulse signals is processed by using freqency division multiplexing technology,different frequency carrier signals are generated to detect dynamic phase changes,to make more detection pulses can be transmitted in optical fiber at the same time.A phase generated carrier differential self-cross division arctangent(PGC-DSD-Arctan)algorithm is proposed for the demodulation of vibration signals.It solves the problem that the demodulation effect is affected by the modulation depth in the traditional algorithm,and has better applicability and higher stability.By building system platform,it can effectively detect and demodulate the phase and frequency information of the 20 kHz vibration signal within a 10 km sensing range.

关 键 词：相位敏感光时域反射计 光纤振动传感 频分复用 信号解调 高频振动检测 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]