The Square Kilometre Array (SKA) will be the largest and most sensitive radio interferometer in the world when it is completed. One of the prime targets for the SKA are radio pulsars, which are powered by the collapsed cores of massive stars - "neutron stars".
With a mass larger than the sun crammed into a region around 25 kilometres across, these objects can rotate many hundreds of times per second (faster than a kitchen blender).
The combination of their fast spin and intense magnetic fields leads to the production of a beam of radio emission, which whirls around with the pulsar's rotation like an immense cosmic lighthouse.
If the pulsar beam intersects the earth, radio telescopes like the SKA can "time" the arrival of the radio pulses very precisely and use them to measure the relative motion of the pulsar and the earth to astonishing precision.
Performing this "pulsar timing" requires a specialised digital signal processor, which accepts a high-speed stream of data from the radio telescope, compensates for distortions imprinted on the signal by the clouds of ionised gas that it has traversed for thousands of years on its way to the earth and folds the corrected signal precisely at the spin period of the neutron star.
The development of the SKA pulsar timing processor is the goal of this project. The result will be a system capable of observing 16 pulsars simultaneously and producing output capable of time-tagging the received radio pulses to an accuracy no worse than two billionths of a second.
To do so, the SKA pulsar timing processor must provide an unprecedented level of control over distortions in the signal processing chain, necessitating the development of new processing algorithms.
The project is being led by Swinburne University in collaboration with the Auckland University of Technology and the SKA Office. In 2019 the design was approved, and construction is expected to start in 2021.
Funding assistance has been provided by the Australian Government through the Department of Industry, Innovation and Science.