European Data Relay System
The European Data Relay System (EDRS) system will be a constellation of GEO satellites intended to relay information and data between satellites / spacecraft and UAVs and ground stations. The system will allow almost full-time communication even with satellites in Low Earth orbit which often have a very reduced visibility from any ground station.
It will make on-demand data available at the right place and at the right time, allowing for example rescue workers to see near-real-time satellite data of the crisis region where they are working in.
The system is being developed as part of the ARTES 7 programme and is intended to be an independent, European satellite system designed to reduce time delays in the transmission of large quantities of data.
The programme is quite similar to the American Tracking and Data Relay Satellite System which was set up to support the Space Shuttle, but EDRS will use a new generation Laser Communication Terminal (LCT) technology. The laser terminal is designed to transmit 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 in order to perform further system- and operational service demonstrations.
The 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 & operations centre, a feeder link ground station (FLGS) and data ground stations.
The first EDRS payload, comprising a laser communication terminal and a Ka band inter-satellite link, will be placed on-board Eutelsat commercial telecommunication satellite, called Eutelsat 9B. The satellite will be launched in 2015 and will be positioned at 9°E.
A second dedicated spacecraft - also carrying a laser communication terminal - will follow in 2015 and will be positioned at 22.5°E. These two parts will form the initial core space infrastructure providing direct coverage for LEO satellites flying over Europe, the Middle East, Africa, the Americas, Asia and the Poles.
Two further spacecraft are planned to complement the system in 2017 and 2019 respectively affording a complete coverage of the Earth and providing long-term system redundancy beyond 2030.
The ground segment of EDRS consists of three ground receiving stations located at Weilheim, Germany, Redu, Belgium and Harwell, UK. The prime Mission Operations Centre will be in Ottobrunn, Germany, while a backup centre will be installed in Redu, Belgium.
The first users for EDRS will be the Sentinel-1 and -2 satellites of the GMES Global Monitoring for Environment and Security programme. The Sentinel satellites will provide data for the operational provision of geo-information products and services throughout Europe and the globe. EDRS will provide the data relay services for the Sentinel satellites facilitating a rapid downlink of large volumes of imagery. Extensive further capacities on the system will be available for third party users.
There are a number of key services that will benefit from this system's infrastructure:
- Earth Observation applications in support of time-critical and/or data-intensive services, e.g. change detection, environmental monitoring.
- Government and security services that need images from key European space systems such as Global Monitoring for Environment and Security.
- Emergency response and crisis intervention applications that need information and data over areas affected by natural or man-made disasters.
- Security forces that transmit data to Earth observation satellites, aircraft and unmanned aerial observation vehicles, to reconfigure such systems in real time.
- Weather satellite services that require the fast delivery of large quantities of data around the world.
EDRS is being implemented as a Public Private Partnership (PPP) between the European Space Agency (ESA) and Astrium. ESA funds the infrastructure development and is the anchor customer through the Sentinel satellite missions. Astrium will carry the overall responsibility for the implementation of the space segment including launch, as well as the ground segment. Astrium will then take over ownership of EDRS and will provide the data transmission services to ESA and customers worldwide.