Gain-tilt in erbium-doped fiber amplifiers and its consequences for distortion in AM systems

摘要

Abstract: Distortions induced by erbium doped fiber amplifiers on optical AM signals are shown, experimentally and theoretically, to originate from the so called locked-inversion gain tilt of the amplifier. The locked- inversion gain tilt may be measured by simple methods, or it may be calculated from a standard steady- state numerical model. It is demonstrated by experiment and calculation that the gain-tilt, and hence the harmonic distortion, may be reduced to acceptable levels by proper design of the fiber amplifier without the need for separate equalization. !15