Investigation of effects of different parameters on the responses and characteristics of fiber bragg grating (FBG) sensors

Due to excellent advantages of low weight, small size, electrically insulative, high resistance to harsh environmental conditions and good line security for telecom applications, Fiber Bragg Grating (FBG) sensors have become indispensable tools in diverse industries such as oil-gas storage and transportation, aviation, and smart bridge applications in order to measure various parameters such as force, pressure, strain, displacement, temperature, humiditiy, and radiation dose. FBG sensors consist of permanent refractive index modulations (fringe patterns) which is occured along the Ge-doped optical fiber core using UV light exposure. FBG sensors have been developed to measure environmental variations by monitoring the changes of optical features (i.e. wavelength, intensity and phase) of a light signal moving inside the fiber. The focus of this research was to explore optimum parameters (i.e. fiber core size with various Ge concentrations and reflectivity rates) which could be the best for manufacturing the ideal FBG sensors. The study also aimed to investigate effects of different parameters on FBG sensors' characteristics and responses in terms of photosensitivity, dB loss at splice points of fibers used and reflectivity. All interactions by experimental work were observed and discussed. Thus, the basis of the optimum FBG sensor manufacturing system used in the study was elucidated.