基于FBG实际反射谱匹配的FBG峰值波长偏移量的高精度确定方法

A High-Precision Method for Determining the FBG Peak Wavelength Shift Based on FBG Actual Reflection Spectrum Match

针对目前光纤布拉格光栅(FBG)解调方案中采用低分辨率CCD测量FBG峰值波长时存在的问题,提出一种采用基于FBG实际反射谱构建基函数匹配CCD测量获得的有限测量点确定FBG峰值波长偏移量的新方法。分别在理论和实测上对这种方法的有效性和可行性进行了研究,证明这种采用FBG实际反射谱函数匹配有限测量数据的方法比采用特定函数拟合测量数据的方法能够更准确地获得FBG峰值波长的偏移量。实现了在CCD采样点数少、光谱分辨率较低的情况下对FBG峰值波长偏移量的高精度确定,有效地提高了实际工程应用中基于低成本CCD解调FBG峰值波长及其微小偏移量的准确性。

Referring to the problems in using low-resolution charge coupled device（CCD） to measure fiber Bragg grating（FBG） peak wavelength,a high-precision method for determining the FBG peak wavelength shift by matching basis function based on the FBG actual reflection and sampling data measured by CCD is proposed.The effectiveness and feasibility of the new method are studied theoretically and experimentally.It is proved that compared with fitting sampling data by specific functions,the matching method based on FBG actual reflection spectrum can determine FBG peak wavelength shift more accurately.In the case of few sampling data and low resolution of CCD measurement,the high-precision determination of FBG peak wavelength shift is achieved.The accuracy of demodulation of FBG peak wavelength shift using low-cost CCD in the practical applications is improved effectively.