Radio signals from cosmic objects have a very wide bandwidth and are generally ‘noise-like’ rather than repetitive. This makes them very different from the telecommunications signals that most off-the-shelf signal-processing systems are designed to handle, so radio telescopes need purpose-built signal processors.
Our ASKAP telescope uses digital processing boards like the one on the right to process 100 Terabits per second – more traffic than the Australian internet.
Our areas of signal-processing expertise include:
- construction of high-speed wideband sampling circuits and digital signal processors, especially for spectrometry
- computer control of signal processors, particularly correlators
- production of highly stable frequency-reference systems for interferometers
- data transfer, especially analogue transfer of very-wide-band signals over fibre optics.
The printed circuit board of a “Redback” signal processing card used in ASKAP is rendered here with the multiple layers colour-coded, revealing its complexity.