Data Transport for the Square Kilometre Array
The future Square Kilometre Array (SKA) radio telescope will present some of the most significant technical challenges faced by the global radio astronomy community in its attempt to construct the largest terrestrial observing instrument conceived to date. The science goals for the array call for high resolution over a wide frequency range (70 MHz to 10 GHz) with antennas concentrated in a core region, and more sparsely distributed antennas in outer regions. The high-frequency dish array will be installed in the Karoo region of South Africa. A low-frequency aperture array, operating at up to 1 GHz and distributed over a few hundred kilometres, will be installed in Western Australia. Signals from each of the antennas in both the dish and aperture arrays will be fed back to a central correlator for processing. The engineering challenges associated with this project are significant, including antenna design for short wavelengths, high resolution, wideband analogue-to-digital conversion and advanced signal processing to generate results from the recovered data. This paper concentrates on the highfrequency dish array to be constructed in South Africa, and the challenges associated with data transport between antennas and the central correlator. It discusses the expected requirements for bandwidth, and the potential architectures and transmission technologies that could be used to meet these requirements.