INVESTIGATIONS OF FIBER NONLINEARITIES INLONG-HAUL OPTICAL WDM TRANSMISSION SYSTEMS

摘要

Wavelength division multiplexing (WDM) has been emerging as an effective techniquefor making use of the full bandwidth offered by optical fiber. To achieve long-haul trans-mission, erbium-doped fiber amplifiers (EDFAs) are employed to compensate for sig-nal attenuation without using optoelectronic/electro-optic conversions. Transmission inthese systems is limited by fiber nonlinearities and amplified spontaneous emission noisefrom amplifiers. In this paper, the long-haul optical WDM system with EDFAs is inves-tigated theoretically. The noise and bit error rate (BER) characteristics of the systemwith optical amplifiers are calculated and the dependence of the BER on interamplifierseparation and input power is shown.