Cumulative waveform distortion in cascaded optical amplifier repeaters for multigigabit IM/DD systems

An analysis was conducted of a cumulative pattern-dependent waveform distortion in cascaded semiconductor laser and Er/sup 3+/-doped fiber amplifiers. At 2.5 Gb/s, cumulative waveform distortion limits the number of cascaded amplifiers to about 20 for the semiconductor amplifiers. The Er/sup 3+/-doped fiber amplifier is relatively unaffected-over 100 stages can be cascaded. The Er/sup 3+/ amplifier is seen to be the better choice for long-haul multigigabit systems.<
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