Comparison of MEO, LEO, and Terrestrial IoT Configurations in Terms of GDOP and Achievable Positioning Accuracies

Abstract

Complementary solutions to the Medium Earth<br/>Orbit (MEO) Global Navigation Satellite Systems (GNSS) are<br/>more and more in demand to be able to achieve seamless positioning worldwide, in outdoor as well as in indoor scenarios,<br/>and to cope with increased interference threats in GNSS bands.<br/>Two of such complementary systems can rely on the emerging<br/>Low Earth Orbit (LEO) constellations and on the terrestrial<br/>long-range Internet of Things (IoT) systems, both under rapid<br/>developments nowadays. Standalone positioning solutions based<br/>on such systems complementary to GNSS can be beneficial in<br/>situations where GNSS signal is highly affected by interferences,<br/>such as jammers and spoofers, while hybrid GNSS and nonGNSS solutions making use of LEO and terrestrial IoT signals<br/>as signals of opportunity can improve the achievable positioning<br/>accuracy in a wide variety of scenarios. Comparative research<br/>of performance bounds achievable through MEO, LEO, and terrestrial IoT signals are still hard to find in the current literature.<br/>It is the goal of this paper to introduce a unified framework to<br/>compare these three system types, based on geometry matrices<br/>and error modeling, and to present a performance analysis in<br/>terms of Geometric Dilution of Precision (GDOP) and positioning<br/>accuracy bounds.