Pulsar Timing for Clock Stability – Exploring an Autonomous and Resilient Approach to Timing Using Radio Pulsars

Abstract

Governments and industries seek autonomous and resilient systems in a world becoming increasingly dependent on digital, interconnected technology. A key example of such is PNT, a fundamental and indispensable utility across the most essential market sector for everyday life. However, PNT is under threat from hostile actors and changing politics, and a system-of-systems approach is required for its delivery. For timing infrastructure, atomic clocks are commonly considered. A network of ground-based atomic clocks support the distribution of the UTC time standard globally. Units have also been utilized onboard multiple GNSS satellites to support timing and ranging services. However, atomic clocks are costly to manufacture, and are demanding to system resources. These challenges have presented significant supply and implementation issues to various nations seeking resilient infrastructure. Atomic clock resource requirements have also led to failures across most GNSS constellations. The focus of this article is the provision of timing by pulsars, a natural source of frequency measurement. Millisecond pulsars in the RF spectrum are highlighted, given much stricter requirements for the measurement of X-ray pulsars on-board a spacecraft. Detection of multiple pulsars are challenging, and so only a single pulsar is considered to synchronize a lower performing clock. The work treats the scenario of lunar PNT, but it may be implemented across other PNT systems. Utilizing a large, origami folded radio antenna deployed on a spacecraft, it could potentially deliver timing performances below 1 µs independent of a synchronization source.