分布式光纤传感技术能够实现连续感知和无盲区测量而获得高度关注。通常基于瑞利散射技术的信号光非常微弱，且存在随机涨落问题，虽然通过相干解调技术可以提高探测灵敏度，但光纤干涉技术还受偏振衰落等问题的困扰，使得系统的定位精度、测量长度、测量速度等指标相互制约。微波光子学将光子学的宽带特性与电子学的易控特性结合，已在通信领域发挥重要作用，本项目将拓展其在传感领域的深入应用，提出将微波加载在连续光波上，在菲涅耳反射信号增强的特种传感光纤中，通过探测反射光在微波域的干涉，实现光载微波干涉的分布式传感新方法。主要研究新型传感理论，信号增强方法和多参量、动静态联合传感的实验验证。本项目利用光纤内部的菲涅耳反射增强信号强度，运用微波干涉技术提高信号稳定性，将克服瑞利散射光信号随机涨落和偏振衰落等问题，有希望获得同时满足较长探测距离、较高空间分辨率和测量速度的新型分布式传感系统，具有重要的科学意义和实用价值。

Distributed optical fiber sensor have got a lot of attention recently, as it can realize continuous measurement with no dead zone. Usually the power of Rayleigh back scattering light is quite weak, together with random statistical fluctuations, although the coherent demodulation technique can improve the sensitivity, the fiber interferometer based on such reflective light still has the problem of polarization fading. So the location accuracy, measuring range and signal bandwidth are interrelated and interact on each other in the sensing system. Microwave photonics has played an important role in optical communication, with the advantages of broadband of photonics and easier modulation of electronics at the same time, which intrigues us to explore the possibility of sensing applications. This proposal is focus on the research of distributed reflective sensing method and its application based on Optical Carrier Microwave Interferometer (OCMI), meanwhile to enhance the signal intentionally by Fresnel Reflection in the sensing fiber. A promising effort is to bring the strengths from both microwave and optics together by detecting the interference of reflected light in the microwave field. The research content include new sensing theory, signal enhancement methods and multi-parameters, dynamic and static joint sensing experiments. We will utilize advanced microwave technology to insure the stability of the interference signal, and further improve the power of reflective light through special fiber structure. This proposal with scientific significance and practical value hopes to realize a new type of distributed sensing system with longer detection range, higher positioning accuracy and faster response speed, overcoming the faults such as low Rayleigh scattering light’s random fluctuation and polarization fading.