Title: Impact of geometry sensitive satellites on the navigation performance of ground-based augmented GPS
Authors: Irfan Sayim; Haoxiang Lang; Dan Zhang
Addresses: Department of Automotive, Mechanical and Manufacturing Engineering, University of Ontario Institute of Technology, GRASP Laboratory, 2000 Simcoe Street North, Oshawa, ON, L1G 0C5, Canada ' Department of Automotive, Mechanical and Manufacturing Engineering, University of Ontario Institute of Technology, GRASP Laboratory, 2000 Simcoe Street North, Oshawa, ON, L1G 0C5, Canada ' Department of Mechanical Engineering, Lassonde School of Engineering, York University, Bergeron Center for Engineering Excellence, 4700 Keele St., North York, ON, M3J 1P3, Canada
Abstract: This paper discussed the impact of geometry sensitive of satellites on the navigation performance of ground-based augmentation system (GBAS). The nominal number of satellites (space vehicles, or SVs), defined in RTCA/DO-229E, in the global positioning system (GPS) constellation was used in the analysis. In the quantification of GBAS navigation performance (i.e., the protection level or PL computed at aircraft), full constellation and one and two SV outage scenarios were applied through the search process within all combinations of healthy SV geometries (i.e., subsets of SVs in view). It was observed that some SV combinations, subset geometries obtained after depletion of constellation reduced GBAS navigation performances significantly. These geometries were treated as unsafe for an initiation of intended aircraft precision approach and landing. Further, SVs affecting the integrity and the availability of GBAS in this manner were identified as 'geometry sensitive'. The impact of geometry sensitive SVs on the GBAS navigation performance were quantified and ranked per outage cases.
Keywords: ground-based augmented system; GBAS; satellite outages; navigation integrity; vertical protection level; VPL; vertical alert limit; VAL; GBAS availability.
International Journal of Space Science and Engineering, 2020 Vol.6 No.1, pp.64 - 81
Received: 19 Oct 2019
Accepted: 18 Feb 2020
Published online: 14 Sep 2020 *