Research Of FBG Temperature Sensing Demodulation System Based On Static Method

IIFiber Bragg grating sensor is a novel optic sensor, it has many advantages, such as anti-jamming of electromagnetism, good isolation, anti-cauterization, wide measure range, so it becomes one of the most promising sensing devices. Developing high precision and low cost fiber grating wavelength demodulation system is the key technology of fiber grating field. Although a large number of researchers in domestic research units have been doing a lot of research on the demodulation methods of fiber Bragg grating sensor, most of the researches are still in the phase of lab experiments and have not yet met the requirements of the practical industrial productions. So the research about demodulation of fiber Bragg grating is the keystone of this paper.The main research works are as follows:(1)Sensing theory and temperature character of fiber Bragg grating is analyzed, domestic and overseas research development of fiber Bragg grating wavelength demodulation system is introduced, a temperature demodulation system of fiber Bragg grating sensor based on the static demodulation method is taken.(2)The hardware design about fiber Bragg grating temperature is taken, such as photoelectrical measure circuit, low-pass filter circuit, A/D conversion circuit, data collection circuit of STC89C52 and serial communications of STC89C52.(3)The software program about the fiber Bragg grating temperature demodulation system is taken, such as program of data collection system, program of serial communication about STC89C52, and serial communication about PC, program of data demodulation and interface of user about PC which are made by VC++. (4)A full experiment about fiber Bragg grating temperature sensing demodulation system based on static demodulation is taken, the designed hardware circuit and software is debugged to demonstrate the validity and the feasibility of the scheme.