锯齿波FMCW光纤声传感器信号解调技术  

Demodulation Technology of the Sawtooth-Wave Optical FMCW Fiber Acoustic Sensor

作　　者：李闯[1] 倪明[1] 张金权[2] 焦书浩[2] 赵锋[2] 郭戈[2] 杨依光[2] 

机构地区：[1]国防科学技术大学光电科学与工程学院,湖南长沙410073 [2]中国石油天然气管道通信电力工程总公司,河北廊坊065000

出　　处：《压电与声光》2012年第5期688-691,共4页Piezoelectrics & Acoustooptics

摘　　要：讨论了锯齿波光源频率调制干涉型光纤声传感器的基本原理及数字化信号解调方案。对传感器信号及其频谱做了理论分析,给出了数字化信号解调流程。并通过实验分析了干涉信号的频谱特征,并在10kHz锯齿波光源频率调制下,对10m和20m臂差的干涉仪并联进行信号解调。实验结果表明,该探测方案无需移频器件即可实现外差检测,改变干涉仪臂差即可实现频分复用,适用于远程,全光,复杂环境下的微弱声振动检测。The principle and architecture of an interferometric fiber acoustic sensor based on sawtooth-wave optical frequency-modulated continuous-wave are introduced.Firstly,the beat signal and its spectrum are theoretically analyzed,and a digital demodulation method is described.Secondly a corresponding experimental system is built to analyze the spectrum.Digital demodulation with 10 m and 20 m arm difference of interferometers is finished under 10 kHz sawtooth-wave optical frequency-modulated.The experimental results show that this sensor is a heterodyne interferometer but without frequency shifters and a frequency division multiplexing system can be easily got by changing the arm difference of interferometers.It can be used in all optical,long-distance faint acoustic vibration detection under complicated condition.

关 键 词：锯齿波 连续波调频 光纤传感器 外差检测 

分 类 号：TN247[电子电信—物理电子学]