Abstract

Wavelength-division-multiplexing (WDM) techniques and the use of dispersion-shifted fibers (DSF) permit the design of ultrahigh-capacity, flexible systems. The most stringent limitation on such systems is due to four-wave-mixing (FWM) effects, which are particularly exacerbated when silica-based optical amplifiers with limited bandwidth are used, because of the subsequent close channel spacing. Proposed strategies for coping with FWM-induced system performance impairments include (a) dispersion-managed fiber routes¹ and (b) unequally spaced in frequency² for eight WDM channels ranging over 7 and 11.6 nm, respectively.

© 1995 Optical Society of America