Who is involved?
The development of EGNOS was managed by the European Space Agency (ESA) under a tripartite agreement with the European Commission (EC) and the European Organisation for the Safety of Air Navigation (Eurocontrol).
The ownership of the EGNOS assets was transferred from ESA to the EC in April 2009 and EGNOS officially entered service on 1 October 2009. The service is delivered, through a contract with the EC, by the European Satellite Services Provider, ESSP SaS, founded by seven air navigation service providers. ESA is the design and procurement agent on behalf of the EC.
What does it do?
EGNOS augments the GPS system. Correction data improve the accuracy of the current GPS services from about 10 m to about 2 m. In addition, EGNOS disseminates, on the GPS L1 frequency, integrity signals in real-time, providing information on the health of the GPS constellation.
EGNOS Coverage Area
For the time being, EGNOS offers good performances in all 27 European member states except for the parts of Spain, Italy, Greece, Bulgaria, Romania, Slovakia, Poland, Lithuania, Finland and Sweden that are located in the northern, southern and eastern extremes of the EU territory. This will be improved in the future. EGNOS also has the inherent technical capability to be extended to Northern Africa and the Middle East, pending the construction of additional ground infrastructure.
EGNOS System Architecture
The system is composed of transponders installed on three geostationary satellites and of a ground network of about 40 positioning stations and four mission control centres, all interconnected.
EGNOS offers or will offer three high-performance navigation and positioning services:
- Open Service
- Safety-of-Life Service
- Commercial Service or "EGNOS Data Access Server" (EDAS)
The Open Service is available since October 2009 and the Safety-of-Life Service is available since March 2011. The Commercial Service or EDAS is currently available on an experimental basis and will be deployed in 2011.
EDAS: Real-time Access to EGNOS
EDAS disseminates EGNOS data in real-time and is the single point of access for the data collected and generated by the EGNOS infrastructure.
EDAS provides three main types of data:
- Raw GPS, GLONASS and EGNOS GEO observations and navigation data collected by EGNOS ground-based monitoring and navigation stations;
- EGNOS augmentation messages, normally received by users via the EGNOS geostationary satellites;
- EGNOS air traffic control messages containing EGNOS, GPS and GLONASS status information and almanacs.
EDAS is already available on an experimental basis and will be deployed in 2011.