Reconstructing the WAAS Undersampled Ionospheric Gradient Threat Model for the WAAS Expansion into Mexico

Ephrem Paredes, Nitin Pandya, Lawrence Sparks, Attila Komjathy

Abstract:	The Wide Area Augmentation System (WAAS) broadcasts vertical signal delay estimates and their confidence bounds on an ionospheric grid. The WAAS ionospheric threat model is a table of numbers that determines the amount by which the confidence bounds at each ionospheric grid point are inflated to protect users from the threat of undersampled gradients in the ionospheric electron density. The recent expansion of WAAS has included the addition of five stations in Mexico, a region characterized by a generally higher level of ionospheric activity. This paper discusses how the inclusion of these Mexican stations has affected the construction of the current "Release 8/9" ionospheric threat model versus the previous "Release 6/7" version
Published in:	Proceedings of the 21st International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2008) September 16 - 19, 2008 Savannah International Convention Center Savannah, GA
Pages:	1938 - 1947
Cite this article:	Paredes, Ephrem, Pandya, Nitin, Sparks, Lawrence, Komjathy, Attila, "Reconstructing the WAAS Undersampled Ionospheric Gradient Threat Model for the WAAS Expansion into Mexico," Proceedings of the 21st International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2008), Savannah, GA, September 2008, pp. 1938-1947.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In