Reduction of the four wave mixing in optically amplified links by reducingpulse overlapping

We report a theory on the four wave mixing that permits to evaluate the sig nal degradation in WDM systems with a bandwidth located at the zero dispers ion wavelength of the fiber link, taking into account the pulse duration of the signal. Numerical simulations confirm this theory showing how systems based on 16 X 2.5 and 16 X 10 Gbit/s can operate also at the zero dispersio n wavelength if the pulse overlapping is limited by the use of suitable val ues of the pulse duration and of the delay among the input signals located at different frequencies. (C) 2000 Elsevier Science B.V. All rights reserve d.