Abstract
This paper demonstrates experimental results for 40-Gbit/s OTDM transmission over single in-line fibre span using unidirectional forward Raman amplification. The experiment uses legacy dispersion-managed SMF-DCF configuration where remote EDFAs are used to compensate for the DCF span losses. We successfully show that the transmission performance improves considerably with forward Raman pumping if we apply the appropriate signal wavelength, Raman pump power and remote EDFAs gain. As a result, repeaterless transmission over 206-km SMF is practically achieved using 1545-nm signal wavelength, 1.6-W Raman power and unsaturated Erbium gain into the DCF spans. We believe that such investigation results can be exploited to upgrade network sections that still use legacy fibres without the need for major alteration.