1.28 Tbit/s (32/spl times/40 Gbit/s) transmission over 1000 km NDSF employing distributed Raman amplification and active gain flattening

Transmission of 32 × 40 Gbit/s ETDM channels has been demonstrated over straight-line 1000 km NDSF with 100 GHz channel spacing and a record 160 and 200 km amplifier spacing. Active Raman gain flattening allowed viable performance without forward error correction, optical regeneration and polarisation interleaving.