本文提出一种基于半导体光放大器(SOA)光纤环形激光器的智能光纤动态应变传感系统,并采用自适应光折变双波混频技术对其进行解调,解调过程中无需对准静态应变和温度进行任何主动补偿。当FBG(Fiber Bragg Grating)传感器的反射光谱因动态应变而发生改变时,则激光输出的波长会相应移动,随后转换为相应的相移并由InP∶Fe光折变晶体双波混频干涉仪解调。实验结果表明,该传感系统能够测量50~464 kHz之间的动态应变且灵敏度高于0.5με Hz ^-1(ε为应变)。在InP∶Fe光折变晶体中同时对三个FBG传感器的动态应变进行解调,实验证实双波混频干涉仪的多路复用是切实可行的。

This paper proposes an intelligent optical fiber dynamic strain sensing system based on a semiconductor optical amplifier (SOA) fiber ring laser, and uses adaptive photorefractive two-wave mixing technology to demodulate it, and there is no need to align the static strain during the demodulation process. And temperature for any active compensation. When the reflection spectrum of the FBG (Fiber Bragg Grating) sensor changes due to dynamic strain, the wavelength of the laser output will move accordingly, then converted to a corresponding phase shift and demodulated by the InP∶Fe photorefractive crystal two-wave mixing interferometer. Experimental results show that the sensor system can measure dynamic strains between 50 and 464 kHz and the sensitivity is higher than 0.5με Hz ^-1(ε is strain). In the InP∶Fe photorefractive crystal, the dynamic strain of three FBG sensors is demodulated at the same time. The experiment proves that the multiplexing of the two-wave mixing interferometer is feasible.