DC9 – Position Navigation and Timing (PNT) using LEO Signals of Opportunity (LEO SoOP)

Partner Organisations

Heriot-Watt University (PhD awarding institution)
Celestia-Uk

Supervisors

Dr. Carol Marsh
Dr. Wenda Li

Description of the Work Project

Satellite navigation is essential for critical applications such as telecommunications, Earth observation and autonomous systems. However, these services currently rely predominantly on Global Navigation Satellite Systems (GNSS), whose signals are vulnerable to interference, jamming, spoofing and outages. As future space missions
demand greater resilience, alternative position, navigation and timing (PNT) solutions are becoming increasingly important.
Recent advances in Low Earth Orbit (LEO) satellite constellations have created new possibilities for using communication signals as Signals of Opportunity (SoOp) for navigation. Compared with GNSS, LEO satellites provide stronger signals, a rapidly changing geometry and growing global coverage, making them attractive candidates for resilient PNT. However, challenges remain in signal modelling, synchronisation, measurement extraction and the integration of heterogeneous observations.
The aim of this project is to investigate Position, Navigation and Timing techniques based on LEO Signals of Opportunity for resilient satellite navigation. The project will develop signal processing algorithms and estimation methods that can exploit existing LEO communication constellations as alternative navigation sources. The research
will evaluate navigation performance under degraded GNSS conditions, assess the impact of constellation geometry and signal characteristics, and investigate integrating LEO SoOp with conventional navigation sensors. The proposed techniques will be validated through modelling, simulation and representative experimental datasets. This will contribute to robust and resilient PNT capabilities for future space missions, while also supporting SPARE’s objective of enhancing the resilience of satellite systems and services.

Core activities

1. Characterization of LEO communication signals suitable for positioning, navigation and timing applications, considering different constellations, frequencies and signal structures.
2. Development of signal processing and estimation algorithms for extracting navigation observables from LEO Signals of Opportunity.
3. Evaluation of positioning accuracy, integrity, availability and robustness under interference, jamming or GNSS outage scenarios.