Laurent Labrunie

Network application and system demonstration of WDM systems with very large spans (error-free 32/spl times/10 Gbit/s 750 km transmission over 3 amplified spans of 250 km)

We present the network applications of WDM systems with very large spans. Enabling technologies are low loss fiber, large launch powers, Raman preamplification and forward error correction. An experiment using all these technologies is presented.

4.16 Tbit/s (104 /spl times/ 40 Gbit/s) unrepeatered transmission over 135 km in S+C+L bands with 104 nm total bandwidth

104 /spl times/ 40 Gbit/s unrepeatered transmission over 135.9 km is demonstrated on S+C+L bands (1492-1596 nm) using S-band lumped Raman amplifiers. The system implements distributed Raman pre-amplification over continuous bandwidth of 104 nm.

25 GHz spaced DWDM 160/spl times/10.66 Gbit/s (1.6 Tbit/s) unrepeatered transmission over 380 km

Unrepeatered transmission of 160 25 GHz spaced channels at 10 Gbit/s over 380 km is demonstrated. The combination of recent advanced technologies, such as DWDM multiplexing/demultiplexing, large pump power, remote amplification, in-line filtering and FEC, allow this record transmission to be achieved.

Raman amplification in unrepeatered submarine systems pushes the limits of distance and bandwidth

Raman amplification is a key technology for unrepeatered transmissions as it allows to widely increase both span length and optical bandwidth in a very simple manner. We review in this paper recent record demonstrations and installed systems where Raman amplification fulfills its role as a mean to reach very long repeaterless distances and to expand into new spectral areas.