光纤光栅传感系统有源时域解调技术

将传感光栅用作环形器光纤激光器的端镜，腔中接一受压电陶瓷(PZT)驱动的具滤波功能的匹配光栅，受正弦波电压信号驱动，通过观察同一驱动周期中激光输出两谷值在时域中的间隔，进而判断作用在传感光栅上的轴向待测应变。在-140-720με范围内，其传感分辨率为1．8με，灵敏度为88．152με／ms。理论和实验均证实该装置的感测结果不受环境温度变化的影响。

Time-Domain Demodulation Technique for Active Fiber Bragg Grating Sensor System

A ring-cavity fiber laser based fiber Bragg grating (FBG) sensor system, in which two FBGs are used, is reported in this paper. One of the employed gratings, acted as the end mirror, is sensor element. Another is used as a tunable filter controlled by a piezoelectric stack, which is driven by an electrical sine wave signal. The measured strain applied on the sensor axially can be judged by observing the interval of the output laser between two notches within a driving period in time-domain. Experiment demonstrated that the sensing sensitivity and the resolution of this system are 88.152 με/ms and 1.8 με respectively, within the work range of from -140 με to 720 με. The perturbation of the environmental temperature was proved not to affect the measured results theoretically. It was verified by experiments.