LEO-PNT Performance Metrics: An Extensive Comparison Between Different Constellations

Abstract

Recent years have shown that Low-Earth Orbit (LEO) satellites are becoming the leading idea for the future of the space industry, gathering heavy investment from technology giants, as seen from several providers of mega-constellations, such as SpaceX (Starlink), Eutelsat (OneWeb), Iridium, or Amazon (Kuiper). LEO satellites are suitable not only for communication purposes, but they also hold a strong potential for Positioning, Navigation and Timing (PNT) applications, as their proximity to Earth results in fast satellite movements in orbit as well as in high received signal strengths, which may translate into better PNT signals compared to already available alternatives. In this work, we show the viability of LEO-PNT constellations by providing a comprehensive performance comparison based on coverage, Dilution of Precision (DOP) and Carrier-to-Noise Ratio (C/N0) metrics between several existing and upcoming constellations, as well as two theoretical LEO-PNT constellations, by considering them as dedicated LEO-PNT systems. Our results show that, among the existing and upcoming LEO constellations, Starlink, OneWeb, Xona and Centispace show great promise forfuture PNT solutions, and that alternative designs that are on par, or perhaps even better, are still possible.