Precise positioning has become increasingly critical for applications ranging from autonomous mobility to resilient infrastructure monitoring. Current Global Navigation Satellite Systems provide global coverage but often suffer from weak signals, urban multipath, and interference vulnerabilities. A new study published in December 2025 in Satellite Navigation journal conducted extensive simulations on Low Earth Orbit satellite-based Positioning, Navigation and Timing systems across representative outdoor environments, evaluating signal power, geometry quality, positioning accuracy and interference robustness under different carrier frequencies, satellite transmission powers and constellation designs.
Researchers from Tampere University and Universitat Autònoma de Barcelona published their comparative analysis https://doi.org/10.1186/s43020-025-00186-5 investigating how different LEO constellation configurations perform in positioning accuracy and interference robustness when operating alone or jointly with GNSS. Using semi-analytical modelling and 192,000 Monte-Carlo simulations, the team evaluated 400 users across European regions in five outdoor scenarios, with key variables including carrier bands, Effective Isotropic Radiated Power levels and constellation geometry design.
The study found that optimized LEO constellations, particularly in hybrid mode with GNSS, significantly improve accuracy and maintain strong performance in urban scenarios where GNSS degrades. Results indicate that an EIRP of 50 dBm is sufficient for high-quality outdoor positioning when operating in L- and C-bands, while 10 GHz platforms require higher power to compensate path loss. Hybrid LEO+GNSS modes show markedly improved stability and reliability according to the research.
Multi-shell constellations such as Çelikbilek-1 and Marchionne-2 delivered a favorable balance between satellite count and global geometry, outperforming single-shell layouts. In harsh urban canyon conditions, GNSS accuracy degraded up to seven-fold, whereas LEO-PNT maintained stable ranging performance with limited loss. Interference resistance also improved, with stronger LEO signal power meaning jammers require far greater intensity to cause equal degradation.
Hybrid designs provided the most significant gains, with combinations such as Çelikbilek-1 + Global Positioning System/Galileo, or CentiSpace-like + BeiDou yielding better Position Dilution of Precision distributions, faster fix availability and broader user coverage. The authors conclude that LEO systems are not aimed at replacing GNSS, but rather to enhance availability and resilience under signal-challenged environments.
The findings suggest a realistic rollout pathway for resilient satellite navigation that could benefit autonomous vehicles, UAV routing, emergency response, precision farming and critical infrastructure monitoring, especially where GNSS falters in interference-dense or high-rise environments. Lower-power LEO transmission also reduces deployment cost, opening access for commercial operators. As global demand for secure PNT grows, the integration of LEO and GNSS could become a cornerstone for next-generation navigation technology.
