Matched FBG Application Research on Dynamic Sensing and Demodulation

By applying Fiber Bragg Grating (FBG) optical band pass filter, FBG dynamic strain demodulation system has been designed and realized with high sensibility, wide frequency range, and short response time. Mounted FBG on a PZT bar, a dynamic strain simulator was constructed. AC voltage applied on PZT is converted to the dynamic variation of FBG Bragg wavelength. The system static transfer characteristic curves, obtained by numerical simulation and experiment, are compared. The system is calibrated through experiment and the transfer characteristic curve fitting is carried out. Fitting coefficient is R²=1, measuring range can reach 0.2 nm (200 muepsiv) , precision 0.6 muepsiv, resolution 0.12 muepsiv. In order to overcome the nonlinearity of matched FBG demodulation characteristic, Polynomial fitting of the system transfer characteristic is proposed. Dynamic strain waveform is reconstructed with system output waveform. The strain to be measured can be got on real-time and the nonlinear distortion is minimized. This electronic document is a "live" template. The various components of your paper [title, text, heads, etc.] are already defined on the style sheet, as illustrated by the portions given in this document.