Analysis of Weak and Strong Fiber Bragg Grating

Because of the importance of fiber Bragg grating in designing new devices to meet a need range of optical communication systems, it has attracted a great deal of attention. Fiber Bragg gratings have become a key technology in many applications. They are widely used in optical communication systems as a narrow band filters, dispersion compensators, fiber’s sensors and dense wavelength division multiplexing. Advanced functionalities of fiber Bragg grating can be achieved by controlling its structural parameters. This paper is devoted to the modeling and simulation of weak and strong fiber Bragg gratings. The simulation is based on the solution of the coupled mode equations. The effect of the structural parameters such as grating length, refractive index modulation and grating period on the reflectivity, spectral bandwidth and maximum wavelength is studied. Additionally, the role of a new parameter, which is known as fringe visibility, that it can play in controlling the spectral response of the grating is also investigated. The results show that the reflectivity increases by increasing the grating length, refractive index modulation, or fringe visibility and will be decreased by increasing the grating period. Additionally, the influence of the spectral bandwidth and maximum wavelength by the changing of the grating’s parameters is also taken into account in studying the two types of fiber grating.