The grating period of Chirped FBG is not constant, but varies along the axial direction. Different grating periods correspond to different Bragg reflection wavelengths, and incident light of different wavelengths is reflected at different positions of the chirped fiber grating, so that the light of different wavelengths will produce an optical path difference after being reflected by the chirped fiber grating. Using this effect of chirped fiber grating, the dispersion compensation of different wavelength signals in long-distance fiber communication can be effectively realized.