Semi-empirical multi-port lattice model for long-period fiber grating analysis under arbitrary temperature...

We propose a semi-empirical model for the complete analysis (spectrum, bandwidth, and wavelength/phase shifts) of a temperature-tuned long-period fiber grating (LPFG) filter. By applying the multi-port lattice model to LPFGs, while deriving and utilizing the empirically determined temperature-dependence of core-to-cladding intermodal dispersions, we achieve a precise, practical means of spectrum analysis. Excellent agreement of the model with the experimental results was obtained over wide spectral ranges.