光纤光栅传感器阵列时域地址查询的信号处理技术

Information Processing Technique for Time-domain Addressing Fiber Bragg Grating Sensor Array

用电光调制器将连续光波调制成脉冲光波 ,借助非平衡Michelson扫描干涉仪将波长漂移信息变为相移信息 ,来自各传感元的信号利用程控延时信号对电子开关通导的控制来实现时域地址查询 ,经带通滤波处理 ,用相位计监测相移进而判断应变的大小。实验证实分辨率为 6nε的 4光栅系统传感灵敏度的实验值为 1 63Deg/με。

An electro-optical modulator was introduced to modulate the continuous light wave into pulses. An unbalance Michelson scanning interferometer was employed to transform the wavelength-shift signal reflected by the Bragg gratings to phase-shift signal. Signal coming from each sensor element was selected by controlling the on-off state of an electrical switch with a programmable delay signal generator and, therefore interrogation for time-domain addressing was achieved. Filtered with a band-pass filter, the measured can be judged by monitoring the phase-shift with a phase meter. Experiment demonstrated that the sensitivity of the 4-element sensor system, which was with a resolution of 6 nΕ, was 1.63 Deg/μΕ.