结合布里渊光时域分析和光时域反射计的分布式光纤传感器  

A Distributed Optical-Fiber Sensor Combined Brillouin Optical Time-Domain Analyzer with Brillouin Optical Time-Domain Reflectometer

作　　者：宋牟平[1] 鲍翀[1] 裘超[1] 叶险峰[1] 

机构地区：[1]浙江大学信息与电子工程学系,浙江杭州310027

出　　处：《光学学报》2010年第3期650-654,共5页Acta Optica Sinica

基　　金：国家自然科学基金(60507002)资助课题

摘　　要：对于普通单模光纤的布里渊散射光,其频移是温度或应变的函数,因此通过检测布里渊频移可得到沿光纤分布的温度或应变。但布里渊散射分布式光纤传感器有光时域分析和光时域反射计两种结构,两者具有不同的性能特点和使用场合,在实际传感应用中需要加以选择,用以实现有效的长距离光纤传感。如何在一个系统中融合这两种分布式光纤传感技术,其关键是产生传感所需的频移参考光或探测光。采用光纤激光器作为单一光源,基于微波电光调制产生频移参考光或探测光,并应用正交偏振控制来抑制偏振相关信号衰弱。在同一系统中实现了25 km普通单模光纤的布里渊光时域分析和光反射计,在5 m空间分辨率下达到3℃的温度分辨率。For standard single-mode optical-fiber Brillouin scattering light,its frequency shift is a function of temperature or strain.So,the temperature or strain of the optical-fiber can be obtained via detecting Brillouin frequency shift.However,Brillouin scattering distributed optical-fiber sensor（DOFS） has two structures of optical time-domain analyzer and optical time-domain reflectometer.These two DOFS structures have their respective performance and application.It is necessary to select either optical time-domain analyzer or optical time-domain reflectometer for the real application,in order to achieve effective distributed sensing.As for the combination of these two structures in one sensing system by using the same optical devices,the key point is to produce the frequency-shifted reference or probe light.A fiber laser is employed as one optical source,a microwave electrooptical modulator is used to produce the frequency-shifted reference or probe light,and a method named with the orthogonal polarization control is adopted to reduce the effect of the optical-polarization-related problem.A laboratorial system of 25 km distributed optical sensor is realized by combining these two structures,with 3℃in temperature resolution,and 5 m in spatial resolution.

关 键 词：传感器 布里渊光时域分析 布里渊光反射计 电光调制 正交偏振控制 

分 类 号：TN247[电子电信—物理电子学]