Comparative Feasibility of Tropospheric Correction for Enhanced Accuracy in Satellite-Based PPP/INS Augmentation

Hideki Yamada, Saya Matsushita, Keito Yoshida, Emi Imada, Mei Ozaki, Tatsuya Nagano, and Satoshi Kogure

Peer Reviewed

Abstract:	Recent advancements in satellite based precise point positioning (PPP) augmentation services have enabled real time precise orbit and clock dissemination. However, approaches to atmospheric correction remain inconsistent, and critically, explicit tropospheric corrections are absent from all major real time broadcast services. This leaves an open question about the feasibility and benefit of broadcasting tropospheric corrections. This study assesses feasibility with a focus on Multi-GNSS Advanced Orbit and Clock Augmentation - Precise Point Positioning (QZSS MADOCA-PPP) signal design. We generate locally estimated atmospheric corrections from QZSS MADOCA-PPP signal, augmenting them with tropospheric delay estimates derived from regional PPP processing. For evaluation we use a tightly coupled PPP/inertial navigation system (INS) framework that suppresses geometric dilution and exposes residual atmospheric modeling errors. A dual frequency PPP/INS comparative analysis is conducted under three configurations: (i) no atmospheric correction, (ii) ionospheric correction only, and (iii) combined ionospheric and tropospheric corrections. As these results, tropospheric constraints primarily reduce vertical offsets by about 48% compared with ionospheric correction only, with negligible impact on the horizontal components. Adding tropospheric constraints removes the offset and achieves re-convergence in approximately 60 s. Therefore, the results demonstrate that incorporating explicit tropospheric constraints into satellite based PPP systems is technically feasible and becomes increasingly beneficial when inertial aiding effectively mitigates satellite geometry degradation. These findings constitute one of the first quantitative feasibility assessments of tropospheric augmentation for satellite based PPP/INS and provide practical guidance for future PPP augmentation signal design and PPP/INS system development.
Published in:	Proceedings of the ION 2026 Pacific PNT Meeting April 13 - 16, 2026 Hilton Waikiki Beach Honolulu, Hawaii
Pages:	308 - 317
Cite this article:	Yamada, Hideki, Matsushita, Saya, Yoshida, Keito, Imada, Emi, Ozaki, Mei, Nagano, Tatsuya, Kogure, Satoshi, "Comparative Feasibility of Tropospheric Correction for Enhanced Accuracy in Satellite-Based PPP/INS Augmentation," Proceedings of the ION 2026 Pacific PNT Meeting, Honolulu, Hawaii, April 2026, pp. 308-317. https://doi.org/10.33012/2026.20616
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In