Availability Analysis of Differential Positioning in LEO PNT

Wonwoo Park, Hyunwoo Kim, Byungwoon Park

Peer Reviewed

Abstract:	A fully deployed dedicated LEO-PNT system is an ideal service concept, but establishing the required operational environment in the near term is difficult because many elements must be realized simultaneously, including satellite manufacturing and launch, operational infrastructure, a global reference-station network, a precise orbit determination framework, and a mature user-terminal ecosystem. As an alternative, Low Earth Orbit (LEO) Signals of Opportunity Positioning (SOP) based Positioning, Navigation, and Timing (PNT) that leverages signals from already-operational LEO communication constellations can be considered to exploit the advantages of LEO-PNT in advance. However, SOP-based approaches inherently face structural limitations such as large orbit errors from Two-Line Element (TLE) / Simplified General Perturbations 4 (SGP4) based prediction and uncertainty in satellite clock synchronization. This paper is motivated by the observation that, in SOP environments, the dominant orbit prediction errors exhibit periodicity similar to the orbital period. We estimate the principal periodic components via Fast Fourier Transform (FFT)-based spectral analysis and design an orbital-period-based error compensation model. The proposed model is integrated into a differential doppler based positioning algorithm, and its performance improvement in SOP environments is quantitatively evaluated. In addition, we show that, even in dedicated LEO-PNT environments, reference station based differential techniques provide a practical means to mitigate residual orbit errors, clock errors, and atmospheric delay errors, and we validate this by simulation.
Published in:	Proceedings of the ION 2026 Pacific PNT Meeting April 13 - 16, 2026 Hilton Waikiki Beach Honolulu, Hawaii
Pages:	674 - 681
Cite this article:	Park, Wonwoo, Kim, Hyunwoo, Park, Byungwoon, "Availability Analysis of Differential Positioning in LEO PNT," Proceedings of the ION 2026 Pacific PNT Meeting, Honolulu, Hawaii, April 2026, pp. 674-681. https://doi.org/10.33012/2026.20572
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In