光纤光栅传感器阵列有源时域地址查询技术

报道了一种基于环形腔光纤激光器和1×4模拟电子开关的具备实时监测功能的光纤光栅传感网络查询技术,利用级联的波分复用光栅串充当环形腔光纤激光器端镜,借助可调法布里珀罗滤波器对反射的信号光进行扫描,调整光路结构并增加抽运光强度使信号光得到足够的增益,则可获得各传感元工作波长的激光脉冲,且依时序输出。又引入1×4模拟电子开关,将转换为电信号的激光输出按时序分配至4个输出信道。结合非平衡扫描干涉解调技术,实现了对4光栅传感阵列的查询解调。1555 nm波长时系统传感灵敏度的实验值为1.630°/με,与理论值1.674°/με基本吻合。

Active Time-Domain Addressing Technique for Fiber Bragg Grating Sensor Array

A novel interrogation technology with the function of real-time monitoring for fiber Bragg grating (FBG) sensor system based on a ring-cavity fiber laser, and a 1×4 analog electronic switch is reported. A cascaded wavelength-division-multiplexed FBG sensor array is acted as the reflector of the laser. Letting signal light obtain sufficient gain by adjusting the optical route and increasing the intensity of pump light, then laser pluses working at Bragg wavelength of each element will output orderly by introducing the technique of wavelength scanning with a tunable Fabry-Pérot filter. A 1×4 analog electronic switch is employed. The laser pluses are allocated to 4-output channels in time-sequence. Demodulated with an unbalanced Michelson scanning interferometer, a 4-element array is addressed successfully. Working with a wavelength of 1555 nm, the system is demonstrated to be with a sensing sensitivity of 1.630°/με, which agrees with the theoretical value of 1.674°/με.