Demonstration of 52-nm gain bandwidth over 2400 km (540 dB loss) with gain-equalized low-noise wide-band EDFA's

We successfully demonstrate the compensation of 540-dB transmission loss over 52-nm gain bandwidth by using acoustooptic tunable filters in conjunction with silica-based low-noise wide-band amplifiers. A signal-to-noise rate of over 17 dB (optical) over the whole gain bandwidth has been achieved with very small gain variation (4.3 dB), which corresponds to only 0.8% of the total accumulated gain in the 30 erbium-doped fiber amplifier link.