基于Sagnac原理的单轴分布式光纤传感系统偏振态分析

针对Sagnac干涉型单轴分布式光纤传感器中使用单模光纤作为传感器件时,由于传输光偏振态在双折射影响下所带来的干涉信号“偏振诱导衰落”问题,运用琼斯矩阵分析法,建立了该型传感器系统在传感光纤双折射和外部事件共同作用下,传输光的偏振态对系统功率传输系数影响的数学模型;仿真分析了在传感光纤线性双折射和圆双折射共同作用下,传输光的偏振态对系统功率传输系数的影响;提出了使用法拉第旋转镜提高系统抗偏振能力的改进方法.仿真结果表明,该方法能很好地消除光纤线性双折射和圆双折射.

A Research on Polarization Effects in the Single Distributed Optical Fiber Sensor Based on Sagnac Interferometer

A simulation and an analysis,based on Jones matrix,were presented to study the polarization effect of the single distributed optical fiber sensor which was based on Sagnac interferometer for distributed disturbance detection.And the result shows that the fiber sensor with a Faraday Rotation Mirror can remove the linear birefringence,and the orientation birefringence.So the system is well against the polarization fading and the input light can be linearly polarized to a discretional angle.