3D simulation of transmission and reflection spectra with FIMMPROP software We will show here how FIMMPROP can be used to model fiber Bragg gratings. In this topic, we demonstrate how to simulate fiber Bragg grating (FBGs) using MODE'. The refractive index contrast, as well as the pitch and duty. The work is devoted to the consideration of methods for determining the strain of objects using fiber Bragg gratings under a high-frequency vibration or pulsed mechanical action, which is difficult to perform using widespread methods and devices. The simulated Gauss SFBGs are used to generate a nonuniform sensing pulse train during each scanning cycle.