{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T04:28:52Z","timestamp":1789792132368,"version":"4.0.1"},"reference-count":21,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2016,1,16]],"date-time":"2016-01-16T00:00:00Z","timestamp":1452902400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>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.<\/jats:p>","DOI":"10.3390\/s16010111","type":"journal-article","created":{"date-parts":[[2016,1,18]],"date-time":"2016-01-18T10:58:33Z","timestamp":1453114713000},"page":"111","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Galileo: The Added Value for Integrity in Harsh Environments"],"prefix":"10.3390","volume":"16","author":[{"given":"Daniele","family":"Borio","sequence":"first","affiliation":[{"name":"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"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ciro","family":"Gioia","sequence":"additional","affiliation":[{"name":"Piksel Ltd Italian Branch, Via Ernesto Breda 176, 20126 Milano (MI), Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,1,16]]},"reference":[{"key":"ref_1","unstructured":"Kaplan, E.D., and Hegarty, C. 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