基于混沌光纤激光的准分布式布拉格传感网络

Quasi-Distributed Fiber Bragg Grating Sensing Network Based on Fiber Chaotic Laser

提出了一种基于混沌光纤激光器的准分布式布拉格光纤光栅传感系统,将波长可调谐的混沌光纤激光器作为传感光源,全同弱反射布拉格光纤光栅作为传感元件。利用混沌光源具有delta函数的自相关特性,将混沌源的参考光信号与从全同弱反射布拉格光纤光栅反射的光信号经光电探测器进行光电转换,结合相关法对参考光和反射光进行相关运算,根据相关峰的位置对传感器位置进行精确定位。利用混沌激光的可调谐性实现因应力作用而发生变化的全同弱反射光纤光栅的中心波长的解调,从而实现准分布式的传感网络。实验结果表明利用混沌激光可在单路光纤上复用全同弱反射光纤光栅实现传感,并有望实现密集型全同弱反射光纤光栅传感网络。

A novel type of quasi-distributed fiber Bragg grating sensing system based on fiber chaotic laser is demonstrated. The light source is the wavelength tunable chaotic fiber laser. The identical weak fiber Bragg gratings are utilized as the sensors. According to delta function characteristics of the correlation of chaotic light sources, the correlation peaks of the cross-correlation between the reflected light from sensors and reference light from chaotic fiber laser can locate the positions of the sensors. The center wavelength of the identical weak fiber Bragg grating with stress can be demodulated by using tunable optical fiber grating filter and the quasi-distributed fiber Bragg grating sensing system is realized. The experimental results show that the single fiber link of the identical fiber Bragg grating sensor using the tunable chaotic fiber laser is realized and it is expected to achieve the intensive weak fiber grating sensing network.