SBAS Time-Correlated Error Characterization for Sequential Position Error Overbounding

Leslie Montloin, Fabrice Legrand, Frédéric Bauer, Guillaume Buscarlet, Mickael Dall’Orso, Carlos Lopez de Echazarreta

Abstract:	GNSS-based sequential positioning filters, such as Kalman Filters, are extensively used by land-based applications, such as rail-applications (Brocard, P. (2016)), automotive (European GNSS Agency (2015)) and in other domains such as drones. GNSS and inertial navigation system (INS) hybridization schemes through Kalman filters are also of interest for civil aviation for robustness against jamming and spoofing. In addition, there is a growing interest for land-based applications to fulfill medium to high integrity requirements while maintaining good availability performances. This is because most of these applications are safety-related or liability-related applications. Satellite based augmentation system (SBAS) is currently used by safety-related applications (such as civil aviation) since it delivers ionospheric and/or GNSS satellite orbit and clock corrections, along with integrity bounds on the SBAS residual errors and integrity flags on SBAS products. This enables SBAS users to compute integrity bounds in the position domain, and to fulfill integrity requirements. However, integrity information contained in current and future SBAS messages are designed for user applying snapshot positioning filters that are Weighted Least Square filters. In order to prepare the extension of SBAS to users applying Kalman Filters for high integrity applications, it is of interest to identify SBAS satellite orbit and clock residual error model adapted to time-recursive filters. The goals of this work are to propose a methodology to develop such model and to identify the main parameters influencing the model values. This methodology is targeted for the EGNOS next generation, but is applied in this paper on the European SBAS system (EGNOS V3) dual-frequency satellite orbit and clock residual errors in order to get first EGNOS V3 error model adapted to Kalman Filters. Simulation results presented in this paper provide the model values for the different GPS satellites and assess their sensitivity with respect to the user location in the integrity coverage.
Published in:	Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023) September 11 - 15, 2023 Hyatt Regency Denver Denver, Colorado
Pages:	510 - 530
Cite this article:	Montloin, Leslie, Legrand, Fabrice, Bauer, Frédéric, Buscarlet, Guillaume, Dall’Orso, Mickael, de Echazarreta, Carlos Lopez, "SBAS Time-Correlated Error Characterization for Sequential Position Error Overbounding," Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023), Denver, Colorado, September 2023, pp. 510-530. https://doi.org/10.33012/2023.19222
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In