Simulation of Long-Period Fiber Gratings and Bragg Gratings with MATLAB Implementation

This MATLAB simulation program provides robust modeling capabilities for both long-period fiber gratings (LPFGs) and Bragg gratings, essential components in fiber optic systems. The implementation includes coupled-mode theory algorithms to simulate light propagation through periodic grating structures. For long-period fiber gratings, the code models mode coupling between core and cladding modes, enabling analysis of filtering characteristics and sensing applications through transmission spectrum calculations. Bragg grating simulations employ transfer matrix methods to characterize wavelength-selective reflection properties and phase matching conditions. The simulation environment allows performance evaluation under varying operational conditions including temperature fluctuations (modeled via thermo-optic coefficients), mechanical strain (using photoelastic effects), and refractive index modifications. The program incorporates optimization routines for grating design parameters such as period length, modulation depth, and grating length to achieve desired spectral responses. Key functions include spectral analysis algorithms, parameter sweep capabilities, and visualization tools for transmission/reflection spectra. This computational tool enables researchers and engineers to conduct virtual experiments, optimize grating designs before fabrication, and analyze sensitivity characteristics for sensing applications. The modular code structure facilitates customization for specific grating geometries and material properties, supporting advanced research in optical communication systems and fiber optic sensor development.