62/spl times/42.7 Gbit/s (2.5 Tbit/s) WDM signal transmission over 2200 km with broadband distributed Raman amplification

Transmission of 62 electrically time-division multiplexed 42.7 Gbit/s channels over 2200 km using in-line distributed Raman amplification is described. It is verified that bidirectional-pumped distributed Raman amplification, which is suitable for broadband amplification, enables 40 Gbit/s wavelength-division multiplexed signals to be transmitted within the C- and L-bands.