Measurement of ASE in an in-line EDFA

To achieve population inversion an EDFA uses stimulated emission process where incident photon and emitted photon have same phase. But, alongwith the stimulated emission that creates gain, the gain medium also produces spontaneous emission, which gives rise to the amplified spontaneous emission (ASE) spectrum of the amplifier []. In this paper we have considered the setup to measure amplified spontaneous emission in an in-line EDFA. The effect of pump power and doping radius is studied on ASE at pump wavelength of 1480nm. Also the ASE spectrum is observed with increased number of fiber spans. It has been observed that the ASE power increases with increase in pump power and EDFA length. It is further observed that increasing the doping radius reduces ASE power. The ASE spectrum peak is found to shift to longer wavelengths with increased number of fiber spans. The simulation has been done using optsim 5.2 software.