Ultra-low noise index bidirectional relay system for optical fiber time-frequency synchronization

The invention discloses an ultra-low noise index bidirectional relay system for optical fiber time-frequency synchronization, which is characterized by comprising a dispersion compensation part, a forward signal amplification part, a backward signal amplification part, a first coarse wavelength division multiplexer and a second coarse wavelength division multiplexer, wherein the first coarse wavelength division multiplexer and the second coarse wavelength division multiplexer have filtering functions. According to the invention, the dispersion compensation part is used for compensating the dispersion effect of an optical fiber link; the coarse wavelength division multiplexer is used for realizing bidirectional signal separation and combination; bidirectional compensation is carried out onthe attenuation of the optical fiber link by utilizing the forward and backward amplification parts; and the amplification parts utilize a bipolar structure unidirectional erbium-doped fiber amplifierto obtain an ultra-low no