Radio Astronomy Technologies
Technologies to develop new radio telescopes and to upgrade existing facilities
Square Kilometre Array (SKA), Australia Telescope
Square Kilometre Array (SKA)
Australia is contributing to the next generation radio telescope, the SKA, which will have a collecting area of one square kilometre (one million square metres) - about 100 times greater than the biggest present-day instruments. The new telescope is so ambitious that international collaboration is mandatory in its design, construction and operation.
The SKA is a major technological challenge in areas such as antennas and signal processing. Antenna engineers within CSIRO Telecommunications and Industrial Physics (CTIP) are developing a proposal where the one square kilometre collecting area is made up from approximately 100 'stations' (see figure) where each station has 400 separate but identical antenna elements. It is proposed that each element be a 5-metre diameter Luneburg Lens as shown in the figure. The Luneburg Lens provides the ability to have simultaneous widely-spaced multiple beams across the sky; a feature seen by many astronomers as an essential capability for radio astronomy in the 21st century. Few other designs have this capability.
Other technological developments within CTIP relate to the signal processing challenge and especially the design of a large correlator (where the signals from all the individual elements are collected, multiplied and integrated together).
The Australia Telescope consists of eight radioastronomy antennas located across three sites in New South Wales. Six telescopes make up the Compact Array located at the Narrabri Observatory near the town of Narrabri. Each of these antennas has a reflecting surface with a diameter of 22 metres. A further 22-metre antenna, known as the Mopra telescope, is located near Coonabarabran. The eighth antenna in the Australia Telescope array is the Parkes 64-metre-diameter radio telescope. This telescope has been successfully operated since 1961.
Antenna engineers within CTIP play an active role in the on-going upgrades of the Australia Telescope. An example is the 1996 upgrade to accommodate a 13-beam focal plane array on the Parkes radio telescope in order to maintain its world-class position as a state-of-the-art instrument.