Abstract

The bit rate of long-haul soliton transmission using erbium-doped fiber amplifiers (EDFAs) can be strongly increased by using wavelength-division-multiplexed (WDM) signals. In this case, it has been shown that a wavelength spacing close to 0.5 nm is suitable.¹ To our knowledge, the EDFA gain excursion ∂G, which is a key parameter for WDM transmission, has never been estimated in a bandwidth as narrow as 1 nm, because it requires a measurement accuracy close to 0.01 dB. However, we obtained such accuracy by using a circulating loop² to accumulate the gain excursion over several revolutions and then by proceeding with measurement techniques

© 1995 Optical Society of America