Noise characteristics of Er/sup 3+/-doped fiber amplifiers pumped by 0.98 and 1.48 mu m laser diodes

Measured noise characteristics of Er/sup 3+/-doped optical fiber amplifiers pumped by 0.98- and 1.48- mu m laser diodes (LDs) are reported. The noise figures estimated from the beat noise between signal and spontaneous emission are 3.2 dB for pumping by 0.98- mu m LD and 4.1 dB for pumping by 1.48- mu m LD. The beat noise between spontaneous emission components and the spontaneous shot noise for the 0.98- mu m pumping are lower than those for the 1.48- mu m pumping.<
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