method of calculating coupling coefficient for the one-dimensional inverse scattering of FBG

摘要

PURPOSE: A method for calculating an one-dimensional inverse scattering coupling coefficient is provided to increase a degree of TDLP accuracy with equivalent calculation complexity without reducing a layer thickness of a dioxide process. CONSTITUTION: An one-dimensional inverse scattering coupling coefficient, expressed as a coupled mode equation about a frequency response function H() or an inverse Fourier transform G(t) of the H(), is obtained by using the following method. The depth P and layer thickness h for an extrapolation method are determined. The lowest common multiple L of 1, 2,, P+1 is calculated for the P. A wait factor m is obtained from APWP =e1. A coupling coefficient of the layer thickness and a starting point are calculated by using TDLP. The calculated value is confirmed as the coupling coefficient.