25 GHz spacing ultra-dense WDM transmission experimentof1 Tbit/s (100 WDM×10 Gbit/s) over 7300 km using non pre-chirped RZ format

Abstract
1 Tbit/s (100 WDM × 10 Gbit/s) transmission over 7300km with 25 GHz (0.2 nm) channel separation has been achieved using a non pre-chirped RZ format signal. The ultra-narrow channel spacing of 0.2 nm was adopted to fully utilise the bandwidth of the long-distance erbium-doped fibre amplifier chain. As a result, error-free transmission is possible using forward error correction.