光纤传感器中布里渊增益系数与应变关系的理论研究

布里渊功率和应变的关系是分布式布里渊光纤温度和应变传感器的基础之一,而温度和应变又是通过改变布里渊增益系数来影响布里渊信号的功率。目前许多学者认为布里渊增益系数的变化与应变呈线性关系,但是我们通过理论研究和数值模拟发现,布里渊增益系数和应变之间并非一直为线性关系。因此在测量温度和应变时如果把布里渊增益系数的变化与应变近似地当作线性关系将会产生误差。本文基于此原因,对其进行理论研究并通过数值模拟得出各参数对布里渊增益系数变化的影响。

Theoretical analysis of the relating the coefficient of Brillouin gain to strain in the optical fiber sensor

The relation between the power of Brillouin signal and strain is one of the bases of distributed fiber temperature and strain sensors,furthermore the coefficient of Brillouin gain may be changed by the temperature and the strain which will affect the power of Brillouin scattering.The relation between the change of Brillouin gain coefficient and strain is thought to be linear by many researchers,however,it is not always linear based on the theoretical analysis and numerical simulation.Therefore,if the relation between the change of Brillouin gain coefficient and strain is approximatively regarded as be linear when measuring temperature and strain,it can result in bringing errors.For this reason,the influence of the parameters to Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.