Chromatic dispersion has become an enormous obstacle to the development of long-haul high-speed fiber-optic communications.So Dispersion Compensation Fibers（DCF） are usually used to solve this problem

but they are liable to great insertion loss and nonlinear effects.On the basis of analyzing the dispersion compensation principle of the chirped fiber grating

we propose to use it in multi-channel WDM systems so as to realize long-haul repeaterless transmissions

while overcoming the above-mentioned shortcomings.