基于FPGA的双M-Z分布式光纤传感技术研究

发布时间：2018-05-13 06:46

本文选题：分布式光纤传感 + 马赫-曾德　；参考：《长春理工大学》2017年硕士论文

【摘要】：分布式光纤传感技术集传感和传输于一体,可同时探测物理量的空间分布信息和时变信息。因而极适合诸如油气管道、输水管道和桥梁、大坝等大型、长距离设施的实时监测。相比于散色型或萨格奈克型分布式光纤传感系统,马赫-曾德系统具有灵敏度高、实时性好、无盲区等优点,在诸如地下管道等信号微弱的检测中,具有很好的实用和经济价值。大部分的马赫-曾德传感系统都是基于工控机加采集卡的构架来设计的。该模式虽结构简单、易于实现,但采样不足、响应时间长是造成系统空间分辨率低和实时性差的主要原因之一。针对以上问题,本文设计了一套以FPGA为核心的双马赫-曾德分布式光纤传感系统。主要工作如下:首先从光纤弹光效应和干涉原理出发,阐述了干涉型光纤传感系统的工作机理,并分析了双马赫-曾德系统的定位原理和时延估计方法;然后结合窄线宽激光器、光纤无源器件和PIN等器件设计了一套双马赫-曾德光纤系统;最后以FPGA为核心,利用其并行运算能力,结合系统特点优化相关运算,实现了集高速采样(20MHz)、存储、并行运算于一体的高速信号处理系统,单次响应时间不到2秒(30公里检测距离)。联合系统模拟外界微弱振动,检测系统性能。结果表明,系统灵敏度高,实时性强,平均定位误差约为21.7米。对分布式光纤传感系统的小型化及性能提高具有参考价值,有利于广泛的工程应用。
[Abstract]:Distributed optical fiber sensing technology integrates sensing and transmission, and can simultaneously detect spatial distribution information and time-varying information of physical quantities. Therefore, it is very suitable for real-time monitoring of large and long distance facilities such as oil and gas pipelines, water pipelines and bridges, dams and other large distances. The Maher Ceng De system is compared to the dispersive or sgrenk type distributed optical fiber sensing system. The system has the advantages of high sensitivity, good real-time and no blind area. It has good practical and economic value in detecting weak signals such as underground pipelines. Most of the Maher Ceng De sensing systems are designed based on the framework of industrial computer and acquisition card. Although the model is simple and easy to be realized, the sampling is insufficient and response time One of the main reasons for the low spatial resolution and poor real-time performance of the system is the design of a double Maher Ceng De distributed optical fiber sensing system with FPGA as the core. The main work is as follows: firstly, the working mechanism of the interferometric optical fiber sensing system is explained from the optical fiber effect and interference principle. The positioning principle and time delay estimation method of double Maher Ceng De system are analyzed, and a set of double Maher Ceng De optical fiber system is designed with narrow line width laser, optical fiber passive device and PIN and other devices. At last, using FPGA as the core, using its parallel computing power and combining the system characteristics to optimize the related operation, a set of high speed sampling (20MHz) is realized. The single response time is less than 2 seconds (30 km detection distance). The combined system simulates the weak vibration of the outside world to detect the performance of the system. The results show that the system has high sensitivity, high real-time performance and an average positioning error of about 21.7 meters. It is of reference value and is beneficial to a wide range of engineering applications.

【学位授予单位】：长春理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN791;TP212

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