Core Overbounding and its Implications for LAAS Integrity

Jason Rife, Sam Pullen, Boris Pervan

Abstract:	Empirical studies have observed non-Gaussian behavior in pseudorange correction errors for the Local Area Augmentation System (LAAS). This paper introduces an overbounding technique, called core overbounding, designed to validate integrity for error distributions with heavier than Gaussian tails. The core overbounding process generates a conservative representation of the actual error distribution by decomposing the bound into two parts: an explicit function describing the distribution core and an implicit function describing the far tails. For LAAS applications, it is convenient to express the explicit core bound as a Gaussian Core (GC) or as a Gaussian Core with Gaussian Sidelobes (GCGS). These forms balance bound sharpness, important for heavy-tail mitigation, with operational simplicity, necessary for bound broadcast and protection level establishment in a real-time implementation. Analysis using the GC and GCGS bounds indicates that heavy tails have a relatively weak impact on availability for Category I LAAS but a significant impact for Category III.
Published in:	Proceedings of the 17th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2004) September 21 - 24, 2004 Long Beach Convention Center Long Beach, CA
Pages:	2810 - 2821
Cite this article:	Rife, Jason, Pullen, Sam, Pervan, Boris, "Core Overbounding and its Implications for LAAS Integrity," Proceedings of the 17th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2004), Long Beach, CA, September 2004, pp. 2810-2821.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In