EGNOS System Architecture and Service Area

The EGNOS system is composed of several elements that, altogether, receive the GPS signal, compute the information required to increase the precision given by GPS and broadcast the signals through geo stationary satellites.

EGNOS is divided into four functional segments.

As illustrated in the figure below the EGNOS ground segment is composed of:

  • 36 RIMS (Ranging and Integrity Monitoring Stations) - receiving signals from US GPS satellites.
  • 4 MCC (Mission Control Centers) - for processing the data received from the RIMS and producing the differential corrections counting
  • 6 NLES (Navigation Land Earth Stations) - accuracy and reliability data sending to three geostationary satellite transponders to allow end-user devices to receive them.


For the 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.

The space segment is composed of three geostationary satellites:

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

Finally, the user segment is the set of EGNOS ( or SBAS) receivers developed for various types of users.

As it can be seen, although the corrections are computed for the moment to guarantee precision and availability in the service area (as shown in detail in the picture below), the satellites footprint also reach a great part of Brazil which enables the development of collaborations in this domain.