DFS Copernicus

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DFS-Kopernikus ( Deutscher Fernmeldesatellit Kopernikus , after the astronomer Nikolaus Kopernikus ) was the name of three geostationary communication satellites of the Deutsche Bundespost (later Deutsche Telekom ). They have all since been decommissioned and placed in a cemetery orbit .

  • DFS-Kopernikus 1 : 23.5 ° East (1989–1992), later 33.5 ° East (1992–1995)
  • DFS-Kopernikus 2 : 28.5 ° East (1990-2000)
  • DFS-Kopernikus 3 : 23.5 ° East (1992-2002)

The beginnings

In 1982, the Deutsche Bundespost made the decision to set up a national telecommunications satellite system. The production of the satellite was awarded in 1983 to a German industrial consortium called RDFS (later GESAT ), consisting of the companies MBB-ERNO and AEG-Telefunken Message Technology GmbH (ANT) (formerly AEG-Telefunken). As of 1983, ANT belonged to a consortium of Thomson , Bosch , Mannesmann and Allianz insurance.

When development began, they were intended to serve two purposes:

  1. As a telecommunications satellite for telecommunications connections ( telephone , telex , fax , Datex, etc.) within Germany and to Berlin (West)
  2. For the transmission of television images from OB vans to the broadcasting stations and the feeding of television programs into the cable television networks that were being established at the time

The concept included the DFS I and DFS II satellites in geostationary orbit and a replacement satellite on the ground. The position of 23.5 ° East was planned for DFS I and 28.5 ° East for DFS II.

technology

The satellites had a launch mass of approx. 1400–1415 kg and at the beginning of their lifetime in geostationary orbit a mass of 850 kg. Their solar panels had a span of 15.5 meters and delivered up to 1550 watts of electrical power. The communication equipment consists of ten 14/11–12 GHz transponders (plus five as a reserve) and one experimental 30/20 GHz transponder. The transmission power per transponder was 20 watts. The three 11 GHz band transponders ( FSS band) each have a bandwidth of 72 MHz, the seven transponders for the 12 GHz band ( SMS band ) each have a bandwidth of 36 MHz. The price of the Copernicus satellites was then 50 million  US dollars each .

Mission history

After its start on June 5, 1989, DFS-Kopernikus 1 was positioned at 23.5 ° East. On August 1, 1989, he started working. Although it was neither designed nor planned for this, the Deutsche Bundespost used it mainly not as a telecommunications satellite, but as a television satellite . DFS-Kopernikus was supposed to equalize the delays in DBS television caused by construction and postponements, political disputes and the technical loss of TV-SAT  1, and thus prevent the private Astra satellites from penetrating the German television market. The programs 3sat , PRO 7 , West 3 , Tele 5 , Bayerisches Fernsehen , Eins Plus (cultural program) , RTL Plus and the DSR package, which is already being tested, were switched to the satellite to feed into the cable television networks .

After the start of DFS-Kopernikus 2 on July 25, 1990, which was positioned at 28.5 ° East, it took over all telecommunications services remaining on Kopernikus 1 from September 3, 1990, so that all transponders on Kopernikus 1 were occupied with television programs , so u. a. with Teleclub . After the start of Copernicus 3, this replaced Copernicus 1 at 23.5 ° East. Copernicus 1 was moved to 33.5 ° East where it worked as a communications satellite until it got out of control.

DFS-Kopernikus was not designed as a direct-reception satellite. In addition to the three very wide 72 MHz transponders, which were in the frequency range 11.45–11.7 GHz (and thus in the usual FSS frequency band), the seven 36 MHz wide telecommunications transponders in SMS, which were previously unusual for satellite TV, were required for TV transmission -Band 12.5-12.75 GHz can be used. However, the satellite reception systems available at the time for direct reception of the Eutelsat 13 ° east satellite position could not process such a frequency band and therefore had to be upgraded for DFS Kopernikus reception in the SMS band. The Astra system, on the other hand, consistently followed the Eutelsat standard (10.95–11.75 GHz) with its frequency plan (up to Astra 1D).

Many satellite enthusiasts, who at that time had an existing satellite reception system, did not choose the more complex way to switch to DFS-Kopernikus 23.5 ° East, but simply swiveled their reception system from Eutelsat-ECS 13 ° East a few degrees to the left Astra-ECS 19.2 ° East.

Newly installed Kopernikus reception systems - which were mainly propagated by specialist retailers - were not widely used due to a significantly higher price compared to Astra "cheap bowls" sold via hardware stores, although until the start of the Astra 1C satellite and the activation of ARD and ZDF on the Astra system there were more German-language television programs on Kopernikus 3 than on this one.

After the launch of a third Astra satellite Astra 1C , which was positioned parallel to 19.2 ° East and which took place on May 12, 1993, the battle for the German-speaking satellite sky was decided and took place with the activation of ARD and ZDF on August 27, 1993 the Astra satellite system is completed. The three co-positioned Astra satellites made it possible to receive 48 television programs via one antenna and for the first time there were more German-language television programs on the private Astra system than on Copernicus 3. As a result, the Deutsche Bundespost took it off the market relatively quickly Television satellites. The Post's strategy had finally failed.

From then on, only insignificant feeds to cable networks were made for the average satellite viewer. For example, the first broadcasts of the German-language edition of the private children's program Nickelodeon ran on Kopernikus 3 in the summer of 1995 . In addition, the satellite now worked as originally planned as a telecommunications satellite. In 2002, Deutsche Telekom rented the satellite for the rest of its life to the Greek Hellas Sat, where it ran under the name HellasSat 1 until the end of its life in 2003 .

Use after the fall of the Berlin Wall

After the fall of the Berlin Wall , there was a high demand for telephone connections within Germany. As the telecommunication cables and radio links could not be expanded quickly enough, the new DFS-Kopernikus 2 28.5 ° East was meanwhile used as a telecommunication satellite .

The successor

Because no German satellite occupied it, Germany now threatened to lose its orbital position 23.5 ° East. Telekom was not interested in its own new satellite, although there was and is a need for a communications satellite. Therefore, an agreement was signed with the Astra operating company SES . This provides for the operation of an Astra satellite in the German orbital position, which uses the frequencies allocated to Germany there. The Astra 3A satellite began its work in 2002 as the successor to Copernicus 3.

Reception requirements

At the beginning of the 1990s, the Kopernikus satellites could be received in Germany with satellite dishes with a diameter of around 85 cm or more, while the Astra 1A was 60 cm in diameter. In contrast to the Astra 1A, the viewer needed an expensive LNB for DFS-Kopernikus , which covers both the frequency range of 10.95–11.7 GHz (used exclusively by Astra 1A) and the frequency range of 12.5–12.75 GHz could receive. Because of the higher costs and the larger satellite dish required, the Copernicus satellites could not assert themselves in the mass market despite the larger range of programs at the time. The cable television networks of the Deutsche Bundespost were mainly supplied by the Copernicus satellites.

Direct-to-home market shares around 1990 in Germany:

  • Astra : approx. 80%
  • Copernicus: approx. 20%
  • TV-SAT : probably below 1%

Web links

See also

literature

  • Hans-Martin Fischer: DFS Kopernikus - The German telecommunications satellite from Bremen. Volume 1: Configuration and Function . Stedinger-Verlag, Lemwerder 2009, ISBN 978-3-927-697-52-2 .
  • Manfred W. Schulze: DFS Kopernikus - The German telecommunications satellite from Bremen. Volume 2: Development, Missions and Perspectives . Stedinger-Verlag, Lemwerder 2013, ISBN 978-3-927-697-65-2 .