Performance Evaluation of Kinematic Doppler Positioning with LEO Satellites in Urban Environments

The exponential growth in low earth orbit (LEO) satellites presents a great opportunity to perform positioning based on Signals of Opportunity, that is, kinematic Doppler positioning. To reveal whether Doppler positioning with recent LEO constellations, such as Starlink and OneWeb, could serve as an alternative to the Global Navigation Satellite System (GNSS), its accuracy should be examined in various environments. In this paper, we provide numerical results of kinematic Doppler positioning in urban environments where the GNSS suffers from inaccuracy. The inaccuracy may stem from multipath interference, non-lineof-sight signal reception, and poor satellite geometry, as many skyscrapers can block direct signals from GNSS satellites. These skyscrapers may degrade accuracy in Doppler positioning as well by blocking signals from LEO satellites. We develop a tool to simulate limited sky views due to obstructions for a moving vehicle and perform Doppler positioning to examine its accuracy in urban environments. Numerical results using the tool and Starlink orbit information show a positioning accuracy of about 25 meters in an urban environment. To the best of our knowledge, this paper is the first to show positioning accuracy in urban environments with recent LEO constellations.