提出了一种新型的基于光纤Bragg光栅(FBG)的地震检波器。FBG地震检波器传感头由平面弹簧片、质量块和FBG构成。给出了该检波器的力学模型,理论推导与分析了该检波器的幅频特性和加速度灵敏特性,并讨论了影响该检波器灵敏度的主要因素。实验结果表明,该检波器具有良好的线性度、稳定性和耐受性;检波器的频率响应范围为10~140HZ,传感器灵敏度为25.9pm/g,共振频率为167Hz,较符合理论值;最高可检测加速度值大于30g。
A novel fiber Bragg grating(FBG) based seismic sensor is presented in this paper. The FBG seismic sensor head consists of FBG, spring and mass. The mechanical model is demonstrated. The amplitude-frequency and acceleration characteristics of the FBG seismic sensor are theoretically analyzed. The main factors affecting the sensitivity are also given. The experimental results show that the FBG seismic sensor system has excellent stability and high durability. The frequency response range is from 10 Hz to 140 Hz,the resonant frequency is 167 Hz, and the acceleration sensitivity of the FBG seismic sensor is 25.4 pm/g, Which agree with the theoretical values. The maximum detected acceleration is larger than 30 g.