提出一种基于级联长周期光纤光栅(CLPG)的光纤布拉格光栅(FBG)振动传感器动态解调方法。宽带光源发出的光经FBG反射后,进入到CLPG,经过CLPG调制后FBG反射光强会发生变化。通过温度测量实验对监测系统进行静态标定,再将FBG传感器粘贴于铝板表面,采用该系统监测简支铝板结构在低频和高频下的振动信号。系统采集到的动态信号时域波形及频谱与涡电流位移计的测量结果相吻合,表明该监测系统可实现2kHz以下的动态信号测量。 A dynamic demodulation method of fiber Bragg grating (FBG) vibration sensor based on cascaded long periodic fiber gratings (CLPG) is proposed. The light emitted by the broadband light source is reflected by the FBG and enters the CLPG, and the intensity of the FBG reflected by the CLPG modulation changes. The static temperature of the monitoring system was calibrated by the temperature measurement experiment. The FBG sensor was pasted on the surface of the aluminum plate. The system was used to monitor the vibration signal of the simple aluminum structure at low frequency and high frequency. The time domain waveform and frequency spectrum of the dynamic signal collected by the system are in good agreement with the measurement results of the eddy current displacement meter, indicating that the monitoring system can realize the dynamic signal measurement below 2 kHz.