一种长周期光纤光栅边沿滤波线性解调新方法

A Novel Method of Edge Filter Linear Demodulation Using Long-Period Grating in Fiber Sensor System

光纤光栅作为一种新型的传感器件 ,有着巨大的应用价值。利用长周期光纤光栅的滤波特性 ,提出了一种可应用于光纤光栅传感解调的新方法。即利用长周期光纤光栅作为边沿滤波器的基本器件 ,可完成一路或者多路光纤光栅的传感波长解调。该解调方案基于光强度测量 ,适用于动态和静态测量。而且由于采用全光结构设计 ,无须机械部件调谐 ,因此 ,可大大提高解调速度。具有系统反映迅速 ,性能价格比高等优点。经实验 ,实现了在5nm范围内的波长线性解调。测量波长分辨极限为 0 .0 0 2nm ,解调速度数十kHz。

A novel demodulation method of fiber Bragg grating sensor is presented. Based on the filter characteristics of long -period grating, it is used as the filter component of the demodulation system. An experimental system is built up to achieve one or multi channels of sensor demodulation. Using this method based on intensity, it can achieve linear demodulation with a bandwidth of 5 nm. And the resolving wavelength is 0.002 nm, with the demodulation speed up to 10 kHz. The experimental results were analyzed in detail. The advantages of this system are an all-fiber design, quasistatic and dynamic operation, and potential high-speed demodulation.