Since the temperature characteristics of core mode and cladding mode of TFGB are same as those of FBG,and other temperature compensation is unnecessary,the system can achieve dynamical demodulation of FBG strain sensing to eliminate the effect of temperature noise on strain signal by using TFBG as edge filter when the surrounding temperature changes.

A method of fiber Bragg grating (FBG) wavelength detection based on an all fiber Mach-Zehnder edge filter is proposed.

It also uses an optimal edge detection filter plus a three-state transition and judgment mechanism based on double thresholds, which ensure the accuracy in noisy environment and the robustness to changes in absolute levels.