Real-time calibrating demodulation system of fiber Bragg grating sensor

To improve the demodulation precision of fiber Bragg grating(FBG)sensor array,a real-time calibrating demodulation system which is based on narrow band light source inquiring demodulation method and using impervious to temperature regulator with marker,is presented.The signal is gathered into computer by 12 bit A/D and processed by LabVIEW.The peak detection method is searching peak in subsections.Experiments show that the Bragg wavelength demodulation precision of FBG sensor reaches 1pm and is ten multiple higher than precision of system without real-time calibrating module.Then strain measured experiment shows the error is lower than 1.5×10-6 in 1×10-4 range.