A Comparative Study on Indoor Ranging Accuracy of LEO-PNT Systems

Abstract

The prospect of using Low Earth Orbit - Position-Navigation-Timing (LEO-PNT) for indoor applications has been gaining traction in the past years, given the difficulties that Global Navigation Satellite Systems (GNSS) face in these scenarios. Inherently, LEO satellites deliver higher received power than GNSS, assuming similar carrier frequency bands, which translates to better indoor penetration capabilities and the potential of achieving an indoor PNT solution. This paper presents a comparison between various LEO-PNT system designs, comprising the choice of constellation, carrier frequency, and transmission power, and compares their performance to traditional GNSS constellations. Concise system design takeaways are provided given these extensive simulations which shed light on the requirements for LEO systems to provide the PNT solution indoors. These results show the promising potential for LEO-PNT indoors, particularly for carrier frequencies below 1.5 G Hz and using the medium-sized 'Çelikbilek' constellation, along with the challenges to work at higher frequencies such as 4 GHz or 7 GHz, which are envisaged for outdoor applications.