EGNOS system description

EGNOS is divided into four functional segments:

1) The ground segment is composed of the following stations/centres which are mainly distributed in Europe and are interconnected between themselves through a land network.

• 34 (Ranging and Integrity Monitoring Stations RIMS): receive the satellite signals and send this information to the MCC centres. The EGNOS extension program envisages the deployment of 7 additional RIMS mainly in the MEDA region.
  
• 4 MCC (control and processing centres) receive the information from the RIMS stations and generate correction messages to improve satellite signal accuracy and information messages on the status of the satellites (integrity). The MCC acts as the EGNOS system 'brain'
• 6 NLES (stations that access the geostationary satellites): they receive the correction messages from the CPFs for the upload of the data stream to the geostationary satellites and the generation of the GPS-like signal. This data is then transmitted to the European users via the geostationary Satellite

2) EGNOS support segment. In addition to the previously mentioned stations/centres, the system has other ground support installations that perform the activities of system operations planning and performance assessment.

3) The Space Segment is composed of three geostationary satellites:

• Two Inmarsat III satellites.
• One Artemis satellite from the European Space Agency.

4) User segment: set of EGNOS ( or SBAS) receivers developed for various types of users.