摘要
线性滤波器的FBG解调原理是:根据滤波光与参考光的比值和波长之间的关系来判断比值变化时引起的外界物理量的改变。传统的滤波解调系统中对波长和比值的关系按线性处理,而线性滤波器的滤波曲线本身不是完全的线性。实验中,理论上推导出比值和滤波器的透过率之间成正比关系。对温度和应变相对应的比值和波长进行分开处理,应变为零温度发生变化时,波长和比值在数据拟合时加入高次项按非线性处理。温度一定压力改变时对波长和比值按线性处理。拟合结果表明:非线性拟合情况下波长与比值的曲线与滤波曲线相似度很高,不同温度下对应的曲线上,同一比值相对应的波长差相等。
According to ratios of filter light and reference light and the relationships of wavelength, changes of external physical quantities are determined caused by changes of ratios. It is the principle of FBG demodulation of linear filters. For traditional filter demodulation system, the relationships between wavelength and ratios are pro- cessed in linearity. And curves of linear filters are not entirely linear. In the experiment, deduced ratios in theory are directly proportional to the transmissivity of filters. Temperature, ratios corresponding to strains and wavelength are processed separately. When a strain is zero and temperature changes, a high-order item is added during data fitting process, wavelength and ratios are processed in nonlinearity. When the temperature is a constant but pressure chang- es, wavelength and ratios are processed in linearity. Fitting results show that curves of wavelength and ratio are sim- ilar to filtering curves and wavelength differences are equal corresponding to the same ratios at different tempera- ture curves.
出处
《光电技术应用》
2013年第2期36-39,共4页
Electro-Optic Technology Application
基金
山东省省级重点攻关计划项目(WL10K28)
