NOISE-FIGURE OF ERBIUM-DOPED FIBER AMPLIFIERS IN SATURATED OPERATION

We hale developed a simple electrical noise figure measurement techniq ue for the characterization of optical amplifiers. By subtracting the results of noise measurements at identical detected power levels made with and without the amplifier present, we are able to achieve an accu racy of +/-0.3 dB in measured noise figure. Using this technique we ob tain an excellent agreement between electrically and optically measure d noise figures for two 980-nm-pumped, copropagating erbium-doped fibe r amplifiers (EDFA's) operating in saturation.