Editing Satellite navigation (section)

==Augmentation==
[[GNSS augmentation]] is a method of improving a navigation system's attributes, such as accuracy, reliability, and availability, through the integration of external information into the calculation process, for example, the [[Wide Area Augmentation System]], the [[European Geostationary Navigation Overlay Service]], the [[Multi-functional Satellite Augmentation System]], [[Differential GPS]], [[GPS-aided GEO augmented navigation]] (GAGAN) and [[inertial navigation system]]s.

===QZSS===
{{Main|Quasi-Zenith Satellite System}}
The Quasi-Zenith Satellite System (QZSS) is a four-satellite regional [[time transfer]] system and enhancement for [[Global Positioning System|GPS]] covering [[Japan]] and the [[Asia-Pacific|Asia-Oceania]] regions. QZSS services were available on a trial basis as of January 12, 2018, and were started in November 2018. The first satellite was launched in September 2010.<ref name=":2">{{cite web |url=http://qzss.jaxa.jp/is-qzss/qzss_e.html |title=About QZSS |access-date=2009-02-22 |publisher=JAXA |url-status=dead |archive-url=https://web.archive.org/web/20090314085502/http://qzss.jaxa.jp/is-qzss/qzss_e.html |archive-date=2009-03-14 }}</ref> An independent satellite navigation system (from GPS) with 7 satellites is planned for 2023.<ref>{{cite web |title=Japan mulls seven-satellite QZSS system as a GPS backup |url=https://spacenews.com/japan-mulls-seven-satellite-qzss-system-as-a-gps-backup/ |first1=Caleb |last1=Henry |website=SpaceNews.com |access-date=10 August 2019 |date=15 May 2017 |url-status=live |archive-url=https://archive.today/20231209214741/https://spacenews.com/japan-mulls-seven-satellite-qzss-system-as-a-gps-backup/ |archive-date= 9 Dec 2023 }}</ref>

===EGNOS===
{{excerpt|EGNOS}}