10 Gbit/s transmission over a 5800 km optically amplified testbed using low-speed polarisation scrambling and dispersion management

The first generation long-haul optically amplified lightwave systems operating at 5 Gbit/s have been developed. These systems use dispersion shifted fibres and erbium-doped fibre amplifier repeaters operating at around 1558 nm with, typically, +3 dBm output power. The results of 10 Gbit/s transmission experiments over 5800 km using concatenated optical amplifiers are shown. A chromatic dispersion map to minimise nonlinear impairments is used and also polarisation scrambling at 1.3 kHz to minimise polarisation-induced impairments. The effects of fibre nonlinearity are still observed in the form of pulse distortions although band limiting in the receiver limits the effect of this on the bit-error rate. The results of Q measurements over a three hour period are included, indicating the mean Q performance of the system and residual fluctuations. The results suggest that 1O Gbit/s NRZ transmission over transoceanic distances using optical amplifiers is a realistic prospect, particularly if forward-error correction is employed on the system