Performance degradation of erbium doped fibre amplifier induced by terminal reflection

Degradation of the gain and noise characteristics of an erbium doped fibre amplifier induced by terminal reflection is analysed. It is shown that the reflection at the input end seriously affects the noise characteristics; reflections at the input end smaller than -50 dB at signal wavelength of 1535 nm, and smaller than -36 dB at 1553 nm, are required to suppress the noise figure deterioration below 0.5 dB.