基于瑞利散射特征的光频域反射多维多参量密集分布式传感研究

As technologies and societies progress, the requirements of sensor technologies have undergone a profound revolution. The multi-dimensions, multi-parameters, densely distributed sensing is an important direction of development in the sensor technologies, which are embodied in: First, the sensing spatial dimensions need to be changed from the traditional single point, one-dimensional sensors to two-dimensional, three-dimensional and even four-dimensional (including time dimension) field distribution and vectors sensors. Second, dense sensing, namely the sensing spatial resolution requires to be achieved being the centimeter-level. Last, multi-parameter sensing, an equipment requires to be achieved sensing a variety of parameters at the same time. Currently existing methods cannot meet these three requirements including multi-dimension, multi-parameters and densely distributed sensing at the same time. This project aims at the requirements of the applications and deficiencies of the existing methods. This project explores the functional mechanism between Rayleigh scattering signal characteristics in optical frequency domain reflectometry (OFDR) and sensing parameters , addresses the extraction and estimation of the Rayleigh scattering signal characteristics with high spatial resolution, establish a multi-parametric system based on OFDR with integration and decoupling of multi-parameters and solves the key issues of multi-dimensional physics field simulation and verification , the multi-dimensional dense spatial sensing fiber arrangement, the direction of a vector field determination and so on. This project will realize a multi-dimensional densely distributed sensing approach for measuring temperature, stress/strain, displacement, vibration frequency, disturbance and magnetic field using a single mode optical fiber and explore its application in livelihood, defense and science.

随着科技和社会的不断进步，对传感技术的要求发生深刻变革。其中多维多参量密集分布式传感是重要的发展方向之一，主要体现在：首先，传感空间维度需从传统单点、一维发展到二维、三维甚至四维（包含时间维度）的场分布和矢量传感。其次，密集传感，即有效传感点的空间分辨率需达到厘米级。最后，多参量传感，一台设备需实现多种参量的同时传感。现有传感方法难以同时满足多维、多参量、密集分布式传感这三项要求。本课题针对上述需求和现有方法的缺陷，探究光频域反射方法中光纤瑞利散射信号特征与多种传感参量的作用机理，解决高空间分辨率瑞利散射信号特征提取和估计、光频域反射多传感参量系统构建集成和去耦、多维物理场仿真与验证，多维光纤空间密集排布、矢量场方向识别等关键问题，实现一种以普通单模光纤为敏感介质的温度、应力应变、位移、振动频率、扰动、磁场多维密集分布式传感方法，并探索其在国家民生、国防和科技领域的应用。

随着科技和社会的不断进步，对传感技术的要求发生深刻变革。其中多维多参量密集分布式传感是重要的发展方向之一。本课题针对多维、多参量、密集分布式传感这三项要求，提出基于光频域反射（OFDR）的瑞利散射信号特征覆盖力、热、磁、折射率分布式多参量传感机理，包括：基于磁致伸缩材料的OFDR分布式磁场传感机理；本地光频域信号相似度、频移和距离域信号等多瑞利散射特征的提取与分析机理；基于OFDR拉锥光纤的分布式折射率传感机理，其能够实现在毫米量级的分布式测量，这种分布式折射率传感的能力是单点或准分布式的折射率传方法无法实现的。在瑞利散射信号特征提取和识别算法方面，提出基于频谱细化的OFDR高精度分布式传感方法，克服了传感分辨率与空间分辨率矛盾关系，实现了空间分辨率为1cm时，应变分辨率为3微应变；提出基于OFDR多瑞利散射特征信息长距离分布式光纤扰动传感方法，其利用瑞利散射光谱频移特征和瑞利散射在距离域信号的“V”型凹陷特征检测两处同时扰动事件，实现在无光放大时单端OFDR系统可同时探测92 km附近的两处位置扰动事件。 在OFDR多维多参量传感以及光纤排布和封装方式方面，利用Ansys和Maxwell对磁致伸缩材料磁场和力场的模拟，为多维OFDR分布式磁场传感和多维应变传感提供理论基础。提出细径光纤提升分布式应变传感灵敏度，采用“细径-标准”双光纤结合，利用细径单模光纤与标准单模传感特征差异实现应变与温度同时测量方法，且作为OFDR温度应变解耦的新方法；提出采用阿基米德螺旋线的OFDR二维分布式应变传感。综上，OFDR多维多参量密集分布式传感技术扩展了传感领域的传感维度、布设密集度和传感参量数目，实现了不同种类物理、化学、生物参量的多维度密集分布测量，这是传统传感手段难以实现的，在需要精密监控领域如航天航空、国防军事、装备制造、医疗仪器等具有巨大应用潜力。