基于可调高斯型滤波器的光纤光栅振动解调技术研究

 传统的匹配光纤布拉格光栅型光纤光栅波长解调系统具有波长匹配精度低、调节困难和动态测量范围小的缺点。为了克服上述缺点，采用波长可调谐高斯型滤波器代替传统匹配光纤光栅，提出了一种新型的光纤光栅波长解调技术。建立了基于高斯型滤波器的光纤光栅振动解调系统。对不同频率和振幅的周期性振动进行了解调实验。发现当选择合适带宽的滤波器时，透过滤波器的光功率随压电陶瓷上所加电压信号同步且高保真地变化，表明该系统对振动信号实现了有效的解调。该系统同时具有响应速度快、物理结构简单、动态测量范围大的优点。

Vibration demodulation using fiber grating based on tunable Gaussian filter

The fiber Bragg grating (FBG) demodulation system based on the traditional matching FBG technology has the disadvantages of low wavelength matching accuracy, difficult wavelength adjustment and small dynamic measurement range. To overcome these disadvantages, a novel wavelength demodulation technology of fiber grating is proposed by using a tunable Gaussian filter instead of the conventional matching fiber grating. A vibration demodulation system using fiber grating is established based on the Gaussian filter. The vibration demodulation experiments are conducted for periodic vibration with different frequencies and amplitudes. It is found that, when the Gaussian filter with a suitable bandwidth is selected, the optical power of the light passing through the filter varies synchronously with a high fidelity as the voltage signal applied to the PZT varies. This indicates that the system demodulates the vibration signals effectively. Also, this system features high response speed,simple physical framework and large dynamic measurement range.