Fiber Bragg grating period reconstruction using time-frequency signal analysis and application to distributed sensing

The period and length of a fiber grating structure can be reconstructed from its corresponding complex reflection coefficient using time-frequency signal analysis based on Wigner-Ville and spectrogram distributions. We provide an experimental demonstration of this synthesis technique on two fiber grating structures and obtain good agreement between the reconstructed values and those expected based on the parameters used in their fabrication. We then propose and numerically demonstrate how this technique can be applied to distributed strain (or temperature) sensing