Raman amplifier and optical communication system including the same

摘要

The present invention relates to a Raman amplifier and the like which has a structure capable of easily improving the transient response characteristic without depending on the added/dropped signal channels. In the Raman amplifier, a pumping light source supplies forward pumping light of wavelength lambdap0 to a Raman-amplifying optical fiber. A pumping light source supplies N-channel backward pumping light of wavelengths lambdap1-lambdapN to the Raman-amplifying optical fiber. The wavelength lambdap0 of the forward pumping light is less than or equal to the shortest wavelength of the channel wavelengths lambdap1-lambdapN of the backward pumping light. In particular, the power of the backward pumping light and the power of the forward pumping light are arranged such that the effective length Leff of the Raman-amplifying optical fiber for the channel wavelengths lambdap1-lambdapN of the backward pumping light becomes longer than the actual length L.