European Data Relay System

The European Data Relay System (EDRS) system is a planned European constellation of state of the art GEO satellites that will relay information and data between satellites, spacecraft, UAVs, and ground stations. The designers intend the system to provide almost full-time communication, even with satellites in low Earth orbit that often have reduced visibility from ground stations. It will make on-demand data available to, for example, rescue workers who want near-real-time satellite data of a crisis region.

The system is being developed as part of the ARTES 7 programme and is intended to be an independent, European satellite system that reduces time delays in the transmission of large quantities of data. The programme is similar to the American Tracking and Data Relay Satellite System that was set up to support the Space Shuttle—but EDRS will use a new generation Laser Communication Terminal (LCT) technology. The laser terminal transmits 1.8 Gbit/s across 45,000 km, the distance of a LEO-GEO link. Such a terminal was successfully tested during in-orbit verification between the German radar satellite TerraSAR-X and the American NFIRE satellite. It is also embarked on the commercial telecommunication satellite Alphasat to perform further system- and operational service demonstrations and in the operational sentinel satellites part of the European Copernicus Programme.

EDRS infrastructure will consist of two geostationary payloads (two further payloads are in the planning stage), a ground system consisting of a satellite control centre, a mission and operations centre, a feeder link ground station (FLGS), and data ground stations.

The first EDRS payload, EDRS-A, comprising a laser communication terminal and a Ka band inter-satellite link, was placed on-board Eutelsat commercial telecommunication satellite, called Eutelsat 9B. The satellite was launched in January 2016 by a Proton-M rocket and will be positioned at 9°E.

A second dedicated spacecraft, EDRS-C, also carrying a laser communication terminal, will follow in 2017 and will be positioned at 31°E. These two parts will form the initial core space infrastructure that provides direct coverage for LEO satellites over Europe, the Middle East, Africa, the Americas, Asia, and the Poles. Two further spacecraft are planned to complement the system from 2020 onwards, affording a complete coverage of the Earth and providing long-term system redundancy beyond 2030.

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