What is EGNOS?


The European Geostationary Navigation Overlay Service (EGNOS) is Europe's regional satellite-based augmentation system (SBAS) that is used to improve the performance of global navigation satellite systems (GNSSs), such as GPS and Galileo. It has been deployed to provide safety of life navigation services to aviation, maritime and land-based users over most of Europe. 

EGNOS uses GNSS measurements taken by accurately located reference stations deployed across Europe. All measured GNSS errors are transferred to a central computing centre, where differential corrections and integrity messages are calculated. These calculations are then broadcast over the covered area using geostationary satellites that serve as an augmentation, or overlay, to the original GNSS message.

As a result, EGNOS improves the accuracy and reliability of GNSS positioning information, while also providing a crucial integrity message regarding the continuity and availability of a signal. In addition, EGNOS also transmits an extremely accurate universal time signal.

Benefiting numerous market segments

EGNOS is essential for applications where accuracy and integrity are critical. For example, in the aviation sector GNSS alone does not satisfy the strict operational requirements set by the International Civil Aviation Organisation (ICAO) for use in such critical flight stages as final approaches. However, with the addition of EGNOS, which has been certified for civil aviation since 2011, systems such as GPS can satisfy ICAO standards.  

Beyond the aviation sector, EGNOS improves and extends the scope of such GNSS applications as precision farming, on-road vehicle management and navigating ships through narrow channels – to name a few.

Today, EGNOS is benefiting numerous market segments, including aviation, road, rail, maritime, surveying/mapping, location-based services and agriculture.

To learn more about EGNOS and its role in these sectors, visit the EGNOS Segment Pages.