Single-wavelength 40 Gbit/s soliton field transmission experiment over 400 km of installed fibre

40 Gbit/s soliton transmission over 400 km (57 km amplifier spacing) of installed lines without in-line control has been achieved. The maximum transmission penalties for parallel polarised and polarisation division multiplexed soliton transmission were /spl sim/4 and 1 dB, respectively. The transmission distance is the longest ever reported for a field trial with a single wavelength bit rate >20 Gbit/s for any optical transmission format. The polarisation mode dispersion was numerically found to completely dominate the system performance.