中文摘要：

基于边缘滤波解调原理，提出了一种利用双长周期光纤光栅（LPFG）解调光纤布拉格光栅（FBG）振动传感信号的新方法。利用传输光谱叠加后的双LPFG作为边缘滤波器，增大了FBG传感信号解调灵敏度。静态实验结果表明，利用单、双LPFG作为滤波器解调的灵敏度分别为-1．1965dB／nm和-2．4836dB／nm，双LPFG解调的灵敏度约是单LPFG解调灵敏度的2倍。设计制作FBG振动传感器，利用双LPFG作为滤波器进行了FBG振动传感信号的解调实验，结果表明，传感器的动态响应时域信号及频谱与激振信号吻合很好，并具有良好的冲击振动响应。

英文摘要：

The fiber Bragg grating （FBG） vibration system demodulated by double-long period fiber grating （LPFG） is proposed based on the edge filter analysis. The double-LPFG is adopted as filter after the transmission spectra super positioned,in order to improve the demodulation sensitivity. The static experiments illustrate that the demodulated sensitivities using single-and double-LPFG as filter are --1. 196 5 dB/nm and --2. 483 6 dB/nm, respectively. The demodulation sensitivity of the double-LPFG filter is about twice of that of the single-LPFG filter. The FBG vibration frequency detection experiments are carried out using double-LPFG as filter. Experimental results demonstrate that the acquired frequency and impact response signal and the fast Foxier transform of the signal detected by the designed system agree well with the imposed excitation signal. In addition,the impulse response performance is also good.