Erbium doped fiber amplifier with flat high gain and low noise figure

摘要

The present invention relates to an erbium doped optical fiber amplifier having a flat high gain and a low noise figure, and more particularly, to an erbium doped optical fiber amplifier having a first isolator for blocking reverse propagation of incident signal light; A pump LD for applying pumping light; A first WDM for wavelength-splitting the wavelength of the signal light and the pumping light; Amplifying an incident light signal by the pumping light of the pump LD, and having a negative gain slope; A second WDM for wavelength-splitting the amplified signal light into a pump light and a signal light; A filter that attenuates signal light among output signals of the second WDM and has a negative signal attenuation slope; A Midway isolator that prevents the signal light passing through the filter from propagating in the reverse direction and prevents the inflow of the ASE generated in the next stage; A third WDM for receiving a signal light having passed through the Midway isolator as an input and for wavelength-splitting the wavelength of light for pumping that has passed through the second WDM; A second EDF, which amplifies the incident light signal, has a positive gain slope and is comprised of a first EDF and a different kind of material; And a second isolator for blocking the reverse direction of the signal.;According to the present invention, it has a very high gain for the intensity of the incident light and the change of the pump power, and is flat and has a gain characteristic and a low noise figure.