Precise positioning is 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 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 a comparative analysis in December 2025 in Satellite Navigation, investigating how different LEO constellation configurations perform in positioning accuracy and interference robustness when operating alone or jointly with GNSS. The study, available at https://doi.org/10.1186/s43020-025-00186-5, used semi-analytical modelling and 192,000 Monte-Carlo simulations to evaluate 400 users across European regions in five outdoor scenarios.
Results indicate that an Effective Isotropic Radiated Power 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. 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, as stronger LEO signal power means 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. "Our results show that moderate-power LEO constellations can substantially strengthen outdoor positioning without requiring expensive satellite hardware," the authors noted. "Geometry plays a major role—carefully designed multi-shell constellations achieve strong accuracy even with fewer satellites."
The findings suggest a realistic rollout pathway for resilient satellite navigation. LEO-enhanced PNT 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.
