Abstract

The erbium-doped Fiber amplifier (EDFA) is now recognized as a key component in frequency-division-multiplexed (FDM) systems.¹ In FDM systems, an input power change due to dynamic optical frequency assignment causes a saturation-induced cross-talk penalty through the gain dynamics of the EDFA.² To date, the dynamic gain compensation has been performed by pump-power control.³ When the pump power is changed, the wavelength of the pump source is also changed. Particularly in the case of a 0.98-μm pump, the wavelength change of the pump source induces degradation of pump efficiency and noise performance. In this paper we propose a new method of the dynamic gain compensation of the EDFA for FDM systems based on a novel scheme for signal feedback. We also investigate both theoretically and experimentally the feasibility of an EDFA with dynamic gain compensation as an in-line repeater for a 16-channel 622-Mbit/s FDM system.

© 1994 Optical Society of America