An autonomous distributed timing signal in-space as alternative to GNSS time synchronisation

Accurate synchronised time is an essential requirement for many space-based services. Currently, the primary source of synchronised time comes from Global Navigation Satellite Systems (GNSS) in conjunction with on-board clocks. The vulnerability of GNSS centralised system and the lack of reliability of small on-board clocks have made the need for distributed robust alternatives a pressing concern. A dynamic protocol is presented herein enabling efficient time synchronisation to be reached in satellite systems even in the presence of unknown disruptors or attackers. This approach requires neither an external terrestrial reference source, nor any knowledge of the satellite network topology.