基于Sagnac干涉的新型光缆径路探测方法研究  

Research on New-type Fiber-optic Cable Path Detection System Based on Sagnac Interferometer

作　　者：孙强[1] 秦威[1] 孙睿頔 

机构地区：[1]北京交通大学电子信息工程学院,北京100044 [2]北京邮电大学国际学院,北京100876

出　　处：《铁道学报》2014年第4期60-64,共5页Journal of the China Railway Society

基　　金：铁道部科技研究开发计划(2012X013-B)

摘　　要：直埋光缆的路径探测是进行光缆维护、故障检测的一项重要工作,目前,多基于探测加载在光缆加强芯线上的电磁信号实现。本文基于Sagnac光纤干涉效应,提出一种新型的光缆径路探测方法,以分布式光纤传感理论为基础,结合光相位调制技术和软件解调技术,可有效实现对光缆路径的定位和探测。本文阐述了该方法的探测原理与系统构成,分析相应的相位调制与解调技术,并通过搭建相应的软硬件平台,验证该方法的可行性。实验表明,基于Sagnac光纤干涉效应的新型光缆径路探测方法具有较高的探测灵敏度和定位精确度,同时可有效避免电学探测方法具有的电磁干扰问题。Path detection of direct-buried optical cables is an important task in carrying out cable maintenance and fault diagnosis , which is currently often realized by detecting the electromagnetic signals in metallic strengthened wires of fiber-optic cables.In this paper ,the new-type fiber-optic cable path detection method based on Sagnac interferometer was proposed. Combining with the optical phase modulation technology and software demodulation technology ,the distributed optical fiber sensing theory was applied to locate cable posi-tions and detect cable path effectively.T he detection principle and system structure of the proposed method were expounded. The phase modulation and demodulation technology was analyzed. The feasibility of the method was verified by building the corresponding hardware and software platform.Experimental results show that the proposed method has high detection sensitivity and positioning accuracy and can effectively avoid elec-tromagnetic interferences usually occurring with the electric detection method.

关 键 词：径路探测 Sagnac干涉 相位调制 软件解调 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]