The paper presents the results obtained in simulation of fiber Bragg grating (FBG) and long-period grating (LPG) sensors and their applications. Coupled-mode theory and the. Optiwave software can be used in different industries and applications, including Fiber Optic Communication, Sensing, Pharma/Bio, Military & Satcom, Test & Measurement, Fundamental Research, Solar Panels, Components / Devices, etc. First, the sensing mechanisms of the TFBG functionalized with nanofiber films were. Abstract—Fiber Bragg Grating (FBG) sensors are categorized as a reliable solution for industrial temperature monitoring due to their exceptional sensitivity, immunity to electromagnetic interference, and multiplexing capabilities. The wavelength chosen for interrogation of the.