A very high capacity optical fibre network for large- scale antenna constellations: the RETINA project

A combination of flexible optical time division multiplexing and dense wavelength division multiplexing techniques is deployed for realising a reconfigurable multi-Tbit/s data transport network connecting over 13000 telescope antennas. Both short-range and long-range transport in the 1.3 μm and in the 1.5 μm wavelength range, respectively, are explored. Introduction Very high capacity optical data transport networks usually deploy dense wavelength division multiplexing (DWDM) of many wavelength channels, each carrying data speeds up to 40 Gbit/s which is presently the limit achievable by electronic multiplexing. In this way, capacities up to 10.92 Tbit/s in a single fibre have been obtained in laboratory experiments, composed of 273 wavelength channels at 40 Gbit/s each spread over the S-, Cand L-bands in the 1.5 μm wavelength region [1]. Increasing the data speed in a single wavelength channel beyond 40 Gbit/s can be achieved by optical time division multiplexing (OTDM). With polarisation multiplexing and OTDM, a single wavelength channel capacity of 1.28 Tbit/s has been demonstrated [2]. Evaluating the performance of these multi-Tbit/s systems when loading them up to their full capacity is usually only done in laboratory setups of either DWDM or OTDM systems by deploying data pattern generators. In this paper, a very high capacity data transport network is described using a combination of DWDM and OTDM techniques, which will be fully loaded with reallife signals originating from telescope antennas. The routing flexibility in this RETINA network provides options for dynamically reconfiguring the antenna constellation, in order to meet the observation demands of the users and to improve the system’s availability.