基于布里渊散射的光纤分布式温度应变传感系统研究

项目名称： 基于布里渊散射的光纤分布式温度应变传感系统研究

项目编号： No.61074163

项目类型： 面上项目

立项/批准年度： 2011

项目学科： 电工技术

项目作者： 贾磊

作者单位： 山东大学

项目金额： 10万元

中文摘要： 基于分布式光纤传感技术的独特优势，特别是布里渊散射光对温度和应变同时敏感的特性，以普通单模光纤中的布里渊散射信号为研究对象，在分析布里渊后向散射光特性的基础上，采用激光的内调制和电光调制器外调制相结合的独特方法，提高了该传感系统的空间分辨率，并且首次采用了同源外差干涉方法来解调后向散射光信号，该方法避免了一般干涉对两束光强度相近的要求，简化了测试系统，同时采用电方法来分辨布里渊散射信号的频移和强度变化，进而解调出光纤所受温度和应变的大小，相比于传统方法，可在消除光源不稳或光路扰动等外界因素影响的前提下降低成本。整个系统采用独特方法解决了目前基于布里渊散射的光纤分布式温度应变传感系统存在的诸多问题。分布式光纤传感系统不仅可实现大范围信息场的连续实时检测和监控，而且使单位信息的获取成本降低，大大提高了性价比，这使得其在传感技术领域中发挥越来越大的作用。

中文关键词： 布里渊散射；分布式光纤传感器；同源外差干涉；温度应变解耦

英文摘要： Based on the unique advantage of distributed optical fiber sensing technology, especially the characteristics that Brillouin scattering light are sensitive to both temperature and strain, the distributing optical fiber sensing system is designed. The Brillouin scattering signal in general single mode fiber is set as research object. Through analyzing the characteristics of Brillouin backscattering light, a peculiar method which combined with the internal modulation of laser and external modulation of electro-optic modulator is helped to improve spatial resolution. In addition, the homologous heterodyne interferometer is adopted to demodulate the backscattering signal, which can simplify the system and also avoid the restriction of similar light intensity by usual interference. The electric method(electro-optic modulator method?) is used to resolve frequency shift and intensity change of Brillouin scattering signal, then the temperature and strain can be interrogated. Compared with the traditional method, the system is low cost and immune to external influences which caused by disturbance of light source. The system can realize continuous and real-time monitoring of large-scale information fields, and also reduce cost of obtaining unit information as well as improve ratio of performance to price. Those advantages make the distributing optical fiber sensing system play more important role in the field of modern sensing technology.

英文关键词： Brillouin scattering; distributed optical fiber sensor; homologous heterodyne interferometer; decoupling of temperature and strain