Simulation of a Fiber-Optic Bragg Sensor with a Tilted Grid

Abstract

The study considers the problem of developing a fiber-optic Bragg sensor with a tilted grid and its modeling used in buildings. An important feature of this study is that before manufacturing a fiber-optic sensor on an optical fiber, the results of the simulation model will give a clear idea of the actual production parameters for which the sensors are manufactured, taking into account their characteristics. In this development, using a simulation model, the problem of detecting a small wavelength shift in the reflected signal due to deformation changes is solved, providing reproducible measurements despite optical losses and intensity fluctuations. The transfer matrix method was used in the work, which allows taking into account the refractive index profiles of arbitrary shape. The transfer matrix method makes it possible to determine the spectral characteristics of optical components based on the theory of coupled modes and in the matrix description of an electromagnetic wave passing through an optical fiber. As a result of the study, spectral signal power densities and time characteristics of the Bragg lattice were obtained as a result of changes in the voltage, strain and temperature of the lattice. The main contribution of the study is the developed simulation model of the subsystem for fiber Bragg sensors, which shows that the power of the side lobes is completely minimized in the Gaussian reflection spectrum of FBG, and the results of MATLAB (Simulink) are in excellent agreement with the results of the optical lattice.