Wavelength Division Multiplexing (WDM) transmission in dispersion managed fibre links with an aggregate capacity of 1 terabit/s and lengths in the 500-1,000 km range will be studied, including the effect of an All Optical Wavelength Converter (AOWC) located in some intermediate point along the link. The AOWC is considered as a typical component of a transparent network node, regardless of the chosen architecture of the network and of its nodes. One of the main objectives will be the assessment of the maximum signal distortion tolerated by the AOWC at its input, and of the maximum AOWC distortion tolerated by the further propagation down the rest of the link. Three different AOWC solutions will be compared, the results expected being specifications for the AOWC designers and for the fibre link designers. The systems will be tested, part in the laboratory and part in field environments, with WDM granularities of 40Gbit/s and 80Gbit/s.

OBJECTIVES
In the ATLAS project fibre-optic WDM transmission over 500-1,000 km with an aggregate capacity around 1 Tbit/s will be pursued by adopting return-to-zero signal format and the dispersion management technique, without resorting to intermediate regeneration. Transmission of such capacity over the said distances is of interest only within a network where the signal has to cross various intermediate nodes. Many different network architectures are currently under investigation and in many cases it is believed that All Optical Wavelength Converters (AOWC) would improve the overall network performances. The ATLAS project wants to assess the problems encountered when high capacity fibre transmission is associated with an intermediate AOWC, namely what is the maximum signal distortion tolerated at the AOWC input and what is the maximum output distortion tolerated by the further propagation down the rest of the link.