Decentralised Asynchronous Resilient Time Synchronisation for Satellite Networks

Time synchronisation is a key requirement for space-based networks and their services. Currently, in Low Earth Orbit the primary source of time and position data comes from Global Navigation Satellite Systems along with satellites’ on-board clocks. This centralised architecture leaves satellite networks vulnerable to single points of failures and error cascades. To address these vulnerabilities, the Decentralised, Asynchronous, and Resilient Time Synchronisation, or DARTS framework is presented, enabling sparse satellite systems to time synchronise even in the presence of up to 10% of disruptive actors within the network. This approach requires neither an external terrestrial reference source, any knowledge of the satellite network topology, nor knowledge of the number of disruptive nodes present in the system. DARTS is tested on sparse terrestrial and lunar networks of satellites, and its ability to ensure effective convergence is confirmed with and without disruptor nodes.