High Performance GNSS Algorithms for Satellite Based Delivery of RTK at a Continental Scale

Landon Urquhart, Dragos Catalin, Micheal Albright, Hunaiz Ali, Kendall Ferguson, Andre Ebeling, Rodrigo Leandro

Abstract:	Even with the continued expansion and improvement of cellular internet, there are still many locations where the stability of internet is not sufficient for high precision GNSS. In these cases, it is advantageous to use geostationary L-Band satellites due to their constant and widespread coverage as well as support for low-cost hardware. This paper describes u-blox’s high accuracy GNSS correction processor for continental RTK delivered via L-Band satellite. The newly developed processor takes direct advantage of the SPARTN correction format to efficiently estimate a complete set of satellite states and atmosphere corrections on a single-core/single-threaded application. To provide a cost-effective solution for mass market applications, significant effort was made to support heterogenous reference station networks and to minimize maintenance and server costs through. A high-level architecture of the processor as well as internal metrics are presented highlighting the ambiguity resolution, satellite state estimation and atmosphere model representation used in the processor. Results from the South America service region are presented using u-blox’s F9P chipset integrated into a customer product along with the u-blox D9S L-band correction module to demonstrate the fixing rate, horizontal and vertical positioning accuracy of the service.
Published in:	Proceedings of the 38th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2025) September 8 - 12, 2025 Hilton Baltimore Inner Harbor Baltimore, Maryland
Pages:	503 - 510
Cite this article:	Urquhart, Landon, Catalin, Dragos, Albright, Micheal, Ali, Hunaiz, Ferguson, Kendall, Ebeling, Andre, Leandro, Rodrigo, "High Performance GNSS Algorithms for Satellite Based Delivery of RTK at a Continental Scale," Proceedings of the 38th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2025), Baltimore, Maryland, September 2025, pp. 503-510. https://doi.org/10.33012/2025.20361
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