This paper designs and implies a high precision FBG demodulation system which based on F-P etalon. In order to
reduce the influence of the temperature drift effect, the peristaltic effect, and the nonlinear effect of F-P filter in
traditional tunable filter method, F-P etalon is added as dynamical calibration and wavelength reference. Meanwhile
segmentation demodulation which uses ASE spectral characteristics is applied to achieve high accuracy of the center
wavelength of FBG. The experiment shows that the stability, resolution are 0.65pm, 0.23pm, respectively.
Key words: fiber optics; fiber Bragg grating sensor system; tunable Fabry-Perot filter; F-P etalon; spectrum