Noise performance of erbium-doped fiber amplifier pumped at 1.49 mu m, and application to signal preamplification at 1.8 Gbit/s

Direct measurements of the noise figure of an erbium-doped fiber amplifier are described. With an amplifier gain as high as 36 dB, a noise figure as low as 4.1 dB was measured. Noise figures remained below 6 dB for signal wavelengths within the high gain (G>20 dB) region of the amplifier. An optical receiver sensitivity of -43 dBm at 1.8 Gb/s, corresponding to 215 photons/b, was achieved using the fiber amplifier as an optical preamplifier for a direct detection receiver.<
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