Study on distributed Bragg grating strain sensing network

A wavelength scanning demodulation system based on continuous wave tunable frequency is given in this paper. Based on fiber Bragg grating´s (FBG) axial strain character, the practical FBG strain sensor is designed. At the same time, tunable narrow-band light source, which is composed of wide-band light source and tunable optical filter, is adopted to demodulate multiplex signals. This method not only supply wider tunable range but also afford higher signal to noise ratio. A mixture multiplexing method that combines optical frequency domain reflectometry (OFDR) and wavelength division multiplexing (WDM) is proposed to address FBG sensing network. The proposed system scheme is testified to have faster demodulation and higher stability by analyzing theoretically and researching experimentally.