European Data Relay System: Difference between revisions

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Revision as of 18:28, 20 October 2021

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The '''European Data Relay System''' ('''EDRS''') system is a European [[satellite constellation|constellation]] of [[geosynchronous orbit|GEO]] satellites that relay information and data [[inter-satellite radiocommunication|between satellites]], spacecraft, [[Unmanned aerial vehicle|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 makes on-demand data available to, for example, rescue workers who want near-real-time satellite data of a crisis region.

The system has been 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 is using a new generation [[Laser communication in space|Laser Communication Terminal]] (LCT) which carries data at a much larger [[bit rate]]: the laser terminal transmits 1.8 Gbit/s across 45,000&nbsp;km (the distance of a LEO-GEO link), while the TDRSS provides ground reception rates of 600 Mbit/s in the [[S-band]] and 800 Mbit/s in the [[Ku band|Ku-]] and [[Ka band|Ka-bands]].<ref name=ISS-comms-2019>{{Cite web|last=Today|first=Matt |last=Williams, |publisher=Universe Today |title=The ISS Now Has Better Internet Than Most of Us After Its Latest Upgrade |url=https://www.sciencealert.com/the-iss-now-has-better-internet-than-most-of-us-after-its-latest-upgrade|date=26 Aug 2019|access-date=2020-06-23|website=ScienceAlert|language=en-gb}}</ref>

Such a terminal was successfully tested during in-orbit verification between the German radar satellite [[TerraSAR-X]] and the American [[Near Field Infrared Experiment|NFIRE]] satellite.<ref name="TerraSAR-X NFIRE test">[http://www.dlr.de/en/desktopdefault.aspx/tabid-78/7420_read-14120/ TerraSAR-X NFIRE test]</ref> It is also embarked on the commercial telecommunication satellite [[Alphasat]].<ref> [http://telecom.esa.int/telecom/www/object/index.cfm?fobjectid=1138 Alphasat] {{webarchive|url=http://arquivo.pt/wayback/20091223045943/http://telecom.esa.int/telecom/www/object/index.cfm?fobjectid=1138 |date=2009-12-23 }}</ref>