基于多级衍射及自适应补偿的光纤光栅传感器解调技术

The Demodulation Technique of Fiber Grating Sensor Base on Multi Order Diffraction and Adaptive Compensation

解调技术是决定光纤光栅传感解调系统速率、精度、容量等性能的关键因素。提出一种基于线阵光电探测器成像原理的光纤光栅传感器解调方案,通过多级衍射,结合弱曝光自适应超频技术和FPGA并行数据处理技术,实现了对传感信号的快速解调,同时可以实现对级联型光纤光栅传感器和长周期光纤光栅传感器信号的解调。使用温度、应力敏感光纤光栅传感器对搭建的铁路桥模型进行监测,实验结果表明,光纤光栅传感系统的解调精度可以达到10 pm量级,系统可测量光谱范围达50 nm,提高了传感系统的解调速率和精度,同时实现了光纤光栅解调设备的微型化。

Optical fiber grating sensor has been promoted with the wide application of optical fiber grating sensors demodulation system. The demodulation technology has become a key factor of system speed,precision,capacity and other properties. This paper presents a kind of optical fiber grating sensor demodulation technique based on the prin-ciple of linear image sensor,Many problems of demodulation has been solved by multi order diffraction,weak expo-sure adaptive overclocking technology,FPGA parallel data processing technology. All of the technology focus on im-proving the speed of demodulation,the accuracy of demodulation and the Miniaturization. Experiments show that,our system can improve the demodulation precision up to 10 pm,and the spectrum range of demodulation up to 50 nm,It can also demodulate the cascaded fiber Bragg grating sensor and the long period fiber grating sensor.