The systematical research on the fiber optic seismic sensors based on optical Fiber Bragg Grating (FBG) sensing technology is presented in this thesis. Optical fiber sensors using fiber Bragg gratings have a number of advantages such as immunity to electromagnetic interference, lightweight, low power consumption. The FBG sensor is intrinsically sensitive to dynamic strain signals and the strain sensitivity can approach sub micro-strain. Furthermore, FBG sensors are inherently suited for multiplexing, which makes possible networked/arrayed deployment on a large scale.; The basic principle of the FBG geophone is that it transforms the acceleration of ground motion into the strain signal of the FBG sensor through mechanical design, and after the optical demodulation generates the analog voltage output proportional to the strain changes. The customized eight-channel FBG seismic sensor prototype is described here which consists of FBG sensor/demodulation grating pairs attached on the spring-mass mechanical system. The sensor performance is evaluated systematically in the laboratory using the conventional accelerometer and geophone as the benchmark, Two major applications of FBG seismic sensor are demonstrated. One is in the battlefield remote monitoring system to detect the presence of personnel, wheeled vehicles, and tracked vehicles. The other application is in the seismic reflection survey of oilfield exploration to collect the seismic waves from the earth. The field tests were carried out in the air force base and the oilfield respectively. It is shown that the FBG geophone has higher frequency response bandwidth and sensitivity than conventional moving-coil electromagnetic geophone and the military Rembass-II S/A sensor.; Our objective is to develop a distributed FBG seismic sensor network to recognize and locate the presence of seismic sources with high inherent detection capability and a low false alarm rate in an integrated system.
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机译：本文对基于光纤布拉格光栅（FBG）传感技术的光纤地震传感器进行了系统的研究。使用光纤布拉格光栅的光纤传感器具有许多优势，例如抗电磁干扰性，重量轻，功耗低。 FBG传感器本质上对动态应变信号敏感，并且应变灵敏度可以接近亚微应变。此外，FBG传感器固有地适合于多路复用，这使得大规模联网/阵列部署成为可能。 FBG地震检波器的基本原理是通过机械设计将地面运动的加速度转换为FBG传感器的应变信号，并在光学解调后生成与应变变化成比例的模拟电压输出。在此介绍了定制的八通道FBG地震传感器原型，该原型由附在弹簧质量机械系统上的FBG传感器/解调光栅对组成。在实验室中，以传统的加速度计和地震检波器为基准，系统地评估了传感器的性能。演示了FBG地震传感器的两个主要应用。一种是在战场远程监控系统中，以检测人员，轮式车辆和履带车辆的存在。另一个应用是在油田勘探的地震反射调查中，以收集来自地球的地震波。现场测试分别在空军基地和油田进行。结果表明，与常规动圈式电磁地震检波器和军用Rembass-II S / A传感器相比，FBG地震检波器具有更高的频率响应带宽和灵敏度。我们的目标是开发一个分布式FBG地震传感器网络，以识别和定位集成系统中具有高固有检测能力和低虚警率的地震源。
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