光纤光栅空分光复用传感系统的研究

介绍了一种光纤光栅空分复用传感系统,并将光纤光栅的传感特性应用于结构健康检测系统中。宽带光源发出的光波进入光栅阵列时,利用光开关选通不同光路实现FBG空分复用传感系统。系统采用等腰三角形悬臂梁调谐装置对FBG进行挠度加载,利用非平衡M-Z干涉技术对传感信息进行解调,将包含被测应变信息的FBG波长信号转变成相位信号,从而得到被测应变的大小,成功地实现了空分复用传感。该系统可用于静态应变和动态应变的检测,具有高分辨力、大测量范围的特点,其传感分辨率为7.3 nε,灵敏度的实验值为0.82°/με。

Research on spatial division multiplexing of fiber Bragg grating sensors

Controlled by an optical switch, a fiber Bragg grating sensing system based on spatial division multiplexing is developed under a broad-band source illumination. With an isosceles triangle cantilever beam to realize linear tuning of Bragg wavelength of fiber grating without chirping,the system employs an unbalanced Mach-Zehnder interferometer to translate the FBG wavelength signal into phase signal. The strain can be recovered by measuring the phase change with signal processing circuit. With a high resolution characteristic and wide measurement range,this sensor system has the capability of measuring static strain as well as dynamic strain. Experiment demonstrates that the sensing sensitivity of this system is resolution of 7.3/με,and experimental sensitivity of 0.82°/με.