为了评估交叉敏感问题,从光纤光栅的传感原理出发,分析了外界环境对传感器性能的影响,讨论了光纤光栅物理参量随温度、应力和压力的变化情况,提出了基于偏振相关特性的光纤光栅磁场传感器方案。利用耦合模理论,仿真分析了温度、应力和压力对传感系统输出的影响。仿真结果证明,该磁场传感方案对温度和应力是不敏感的,而时变的压力会对磁场测量带来严重的影响,恒定压力则会改变传感器的测量灵敏度。
To estimate the cross sensitivity,the influence of the environmental conditions on the measurement performance was analyzed based on the sensing principle.The variations of grating parameters with temperature,stress and press were discussed.The scheme of measuring magnetic field based on the polarized dependent properties was presented.Using the coupled mode theory,the influences of temperature,stress and press were theoretically analyzed and simulated.The simulated results indicate that this scheme is insensitive to temperature and stress,but the influence of time varying press is serious while the constant press influences the sensitivity.