with regards
The non-uniform (chirped and apodized) grating [1] is divided into Number of Segments uniform gratings. The coupled mode theory is used to calculate the scattering matrix of each uniform segment, and the spectral response of the whole grating is found by connecting the uniform segments using the transfer matrix theory. The apodization functions Gaussian and Hyperbolic tangent are defined with the following parameters:
Gaussian
exp{-ln2[(2.(z-L/2)/s.L]^2}
Hyperbolic tangent
tanh (s.z/L).tanh(s.(1-z/L))+1-tanh^2(S/2)
When the parameter Apodization function is user-defined, you provide a file with the data describing the apodization. The input file is formatted containing two items per line — the length in μm and the apodization value.
but i can not find others for the range of zero to length of the FBG
looking for the response..
with regards