High-speed optical transmission systems

To meet the severe capacity demands in current fiber communication networks, an advanced integration of the high-speed time-division multiplexing (TDM) and multichannel wavelength-division multiplexing (WDM) data transmission schemes is indispensable. This paper describes our R&D activities into high-speed TDM systems of photonic networks. In high-speed TDM systems, fiber dispersion and non-linearity place limits on transmission speed and distance, and management of these fiber effects is the key for higher bit-rate systems. Even in 10 Gb/s systems, to achieve a satisfactory transmission distance, we had to cope with the speed limit of fiber. At the same time, we have reduced the size and cost of transmitters and receivers so they can be used as "network comodities" in small and simple network equipment. In 40 Gb/s systems, we have conducted experiments with several automatic compensation techniques for overcoming the crucial transmission speed limit of optical fibers.