title: Galileo: The Added Value for Integrity in Harsh Environments.
abstract: A global navigation satellite system (GNSS)-based navigation is a challenging task in a signal-degraded environments where GNSS signals are distorted by multipath and attenuated by fading effects: the navigation solution may be inaccurate or unavailable. A possible approach to improve accuracy and availability is the joint use of measurements from different GNSSs and quality check algorithms; this approach is investigated here using live GPS and Galileo signals. A modified receiver autonomous integrity monitoring (RAIM) algorithm, including geometry and separability checks, is proposed to detect and exclude erroneous measurements: the multi-constellation approach provides redundant measurements, and RAIM exploits them to exclude distorted observations. The synergy between combined GPS/Galileo navigation and RAIM is analyzed using live data; the performance is compared to the accuracy and availability of a GPS-only solution. The tests performed demonstrate that the methods developed are effective techniques for GNSS-based navigation in signal-degraded environments. The joint use of the multi-constellation approach and of modified RAIM algorithms improves the performance of the navigation system in terms of both accuracy and availability.
authors.affiliation: European Commission, Joint Research Centre (JRC), Institute for the Protection and Security of the Citizen (IPSC), Security Technology Assessment Unit, Via Enrico Fermi 2749, 21027 Ispra (VA), Italy. daniele.borio@jrc.ec.europa.eu.
authors.forename: Daniele
authors.initials: D
authors.lastname: Borio
authors.affiliation: Piksel Ltd Italian Branch, Via Ernesto Breda 176, 20126 Milano (MI), Italy. ciro.gioia@tin.it.
authors.forename: Ciro
authors.initials: C
authors.lastname: Gioia
keywords: Galileo; RAIM; integrity; multi-constellation; protection levels