GNSS software upgrade enables LEO satellites positioning service
One of the big stories of 2020 was the collapse and subsequent rescue of the OneWeb low earth orbit (LEO) satellite constellation.
The satellites are intended to provide broadband data, but one of the reasons for the deal was the potential to provide an alternative positioning service. This is increasingly important as the UK is no longer part of the European Galileo positioning system that uses satellites at an altitude of 23,222km rather than the 1,200km of OneWeb.
At the time there was a great deal of comment about how the re-purposing of the OneWeb satellites was not possible.
Now, one of the leading researchers has detailed now a LEO constellation such as OneWeb or the SpaceX StarLink could be used to provide a positioning, navigation, and timing (PNT) service that is less susceptible to interference and noise. This would enable a much higher accuracy of 70cm and could be achieved by a software upgrade.
The paper on a Fused Low-Earth-Orbit GNSS, by Peter Iannucci at the University of Texas at Austin and Todd Humphreys, head of the radionavigation lab at the university, details how a scheme to takes the timing signals from the existing GNSS satellite networks and fuse this with the data being delivered to the ground. This would also mean the receivers could be significantly lower cost.
This would provide a continuous assured PNT service over ±60° latitude covering 99.8% of the world’s population with positioning performance exceeding traditional GNSS pseudoranging. This also use less than 0.8% of downlink capacity of the Starlink network.
https://arxiv.org/abs/2009.12334