Under the package, $160.9 million will deliver a Satellite-Based Augmentation System (SBAS) (the technology underpinning GPS) to improve the reliability and the accuracy of positioning data from five metres to 10 centimetres** across Australia and its maritime zone.
...From Minister Kannavan's press release.
I would hazard even this amount is about a hundred million higher than I would expect, considering a lot of the ground infrastructure is already in place and just needs interfacing across departments and industries. Noting, a facility is already in operation from Canberra, transmitting as a reference station for the MTSAT. An uplink is needed on the west coast...and official representations to the Japanese government, accepting the offer of involvment and access to both networks currently in operation.
....however, I am over the moon this is NOT in the hands of AirServices.