THREE INTEGRATED GAINS OF WIDE BANDWIDTH MULTI-PUMPING RAMAN OPTICAL AMPLIFIER: THE MAXIMUM FLATNESS

Moawad, Moawad I.; Eid, Mahmoud M. A.; Mohammed, Abd El-Naser A.; Abd El-Whab, Mahmoud M.A.

doi:10.21608/mjeer.2006.64170

THREE INTEGRATED GAINS OF WIDE BANDWIDTH MULTI-PUMPING RAMAN OPTICAL AMPLIFIER: THE MAXIMUM FLATNESS

Document Type : Original Article

Authors

Dept. of Electronic and Electrical Communication Eng., Faculty of Electronic Engineering, Menoufya University, EGYPT

10.21608/mjeer.2006.64170

Abstract

In the present paper, the performance of wide-bandwidth multi-pumping Raman
optical amplifier employed in high-data rate and long-haul advanced optical
communication systems has been investigated under different pumping and fiber
conditions. Raman gain is designed as straight line-exponential decay form with
small flat maximum gain. Three different gains are defined and investigated.
Multi-pumping number of NR pumps of equal pumping powers and different
pumping wavelengths of equal spacing are investigated. The pumps interactions
are reduced under large channel spacing.
A novel software program is designed to handle the amplifier bandwidth as a
function of the controlling set of parameters. This broad bandwidth of maximum
flatness is deeply analyzed. A wide range of the amplifier bandwidth of good
flatness is obtained up to 278 nm. It is found that higher gains and wide flat
bandwidth can obtained if either the relative refractive index difference, ∆ or NR
or the shift in Raman pumping wavelength, δλR or both of them increase.
Thus, the repeater spacing in long-haul transmission cables designed for ultrawide
wavelength division multiplexing (UW-WDM) can be adjusted for the
employed transmission channels.

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