Space Based Augmentation Service for Opportunistic LEO-PNT

The emergence of satellite broadband communication services has significantly transformed the Signals of Opportunity (SoOP) navigation landscape, enabling the use of dense opportunistic LEO constellations for Positioning, Navigation, and Timing (oLEO-PNT). This paper introduces a novel Space-Based Augmentation Service for oLEO-PNT users, called SBASOLEO. The approach involves deploying SBASOLEO ground stations (SGS) to enhance orbit reconstruction and to retrieve the synchronization parameters necessary to better process SoOP signals transmitted by uncooperative LEO satellites. This data augmentation is facilitated through an auxiliary space-based Non-Terrestrial Network (NTN) infrastructure, which provides wide coverage low-latency data access for both users and ground stations. The study demonstrates the prototype implementation of SGS by integrating the hardware and signal-processing techniques developed by UniBw M at the INSTA facilities with the advanced reduced-dynamic sequential estimation of the LEO orbits. Simulation results foster the potential to improve opportunistic user positioning by granting NTN SGS access to up-to-date orbit and clock products. This proposed approach significantly advances the Opportunistic LEO-PNT technology as a key contributor to space sustainability, shifting the competitive focus from manufacturing new LEO constellations to mastering signal processing, and ultimately improving LEO satellite data dissemination to end-users.