Temperature Demodulation System Based On Fiber Bragg Grating

Fiber Bragg Grating (FBG) has been widely applied in the sensing fields because of its special advantages such as small volume, high-sensitivity, wide dynamic range and so on. How to demodulate the sensing signal, quickly and efficiently, is the key problem of FBG sensing system. Traditional methods, such as high-precision optical spectrum analyzer (OSA), have greatly been restricted practical application of FBG in the project field because of its big volume and high cost. Thus, research on small-volume, low-cost and high-sensitivity demodulation system is a hotspot in the FBG sensing field.The temperature demodulation system raised in this paper included three parts:FBG temperature sensor, FBG analysis module and the application program of temperature demodulation system. The shift of the center wavelength caused by the variation of the environment's temperature is transported to the fiber Bragg grating analysis (FBGA) module by the fiber. In FBGA, the optical signal is changed to the electrical signal. The processed electrical signal is transported to PC by USB data bus. The application program of temperature demodulation system based on PC is designed to receive the sensing data and display the center wavelength. With the temperature calibration formula of the FBG, the information of the center wavelength is transformed to the temperature, realizing the FBG temperature demodulating. The temperature demodulation system established in this paper can do real-time temperature monitoring with small volume and high-sensitivity.