提出了基于可调光纤环形激光器结构,并采用F-P 标准具解调的光纤布拉格光栅(FBG)动态应变传感系统,具有高达60 dB 的光学信噪比。F-P 标准具用来作为一个边缘滤波器探测FBG 波长的漂移,这样的解调方式具有稳定性高的优点。为了提高动态应变测量系统的分辨率,采用了Music 算法进行频谱分析。实验结果显示,在700Hz 时的动态应变分辨率达到了0.1 με/Hz1/2,是传统FFT 算法的10 倍。

A sensing system with a high optical Signal Noise Ratio (SNR) of >60 dB, which is based on a tunable fiber ring laser configuration, is proposed for the dynamic strain measurement. An F-P etalon serving as edge filter is used to detect the wavelength shift of the Fiber Bragg Grating (FBG) sensor. Such a demodulation device has the advantage of stability. In addition, in order to improve the resolution for dynamic strain measurement, a modern spectral analyzing algorithm called Music modern spectrum estimation is adopted. The experimental results show that a dynamic strain resolution of 0.1 με/Hz1/2 at 700 Hz is obtained, which is 10 times better in terms of strain resolution compared with conventional FFT method.