FLUG REVUE March 2006: Galileo test satellite launched

March 2006

GALILEO TEST SATELLITE LAUNCHED

By Matthias Gründer

The launch of the first Galileo satellite was supposed to have been accompanied by a live report, but the unpredictable climate in the steppe of Kazakhstan put paid to that idea. A snowstorm above the destination airport of Krainy forced the special aircraft packed with officials and journalists two days after Christmas to land at the secluded airfield of Korkyt Ata, Kazakhstan, and after a wait of about four hours there was no choice but to fly back to Moscow. There the unfortunate visitors convened the next morning in a conference room in their hotel to watch the perfect launch from Baikonur – where the sun was shining brilliantly! – on television.

Giove-A

The first, 530kg Galileo test satellite, GIOVE-A (Galileo in-Orbit Validation Element), is now in space, having been launched at 6.19am CET on 28 December 2005 on a reliable Soyuz launch vehicle with restartable Fregat upper stage. Since 12 January 2006 it has been transmitting its signals from an orbit of about 23,000 kilometres, marking the start of the space trials of the accurate European satellite navigation system, Galileo. GIOVE-A is not actually a “genuine” navigation satellite, as its main task is “only” to test technologies and protect the frequencies allocated by the International Telecommunications Union. Had the launch been delayed significantly, these frequencies would have been withdrawn and possibly assigned to another applicant. Now that the definition phase is over, the second phase, development and testing of the subsystems, has advanced an important step forwards.

Second test satellite to be launched shortly

Above all, however, it seems that the programme has emerged from the financial and political disputes with which the first phase was beset and is really pushing forwards with the construction of the first civil satellite navigation system in the world. A second test satellite will shortly follow GIOVE-A into space, while the installation of terrestrial mission control elements proceeds in parallel. For example, one of the two Galileo control centres is to be located in Oberpfaffenhofen near Munich; the other has been secured by Italy. The EU states are bearing about one half of the launch financing, to the tune of about Euro 3.5 billion, while the other half is being contributed by industry, attracted by the prospect of lucrative business. Between now and the year 2020 the economic benefits of the system are estimated at around Euro 74 billion, with some 3.6 million users around the globe and annual operating costs of “only” Euro 220 million.

Over the next 20 years, the procurement, operation and use of the system are expected to generate 100,000 jobs in Europe alone, in service companies, software houses and the businesses which will build Galileo receivers for ordinary people. Yet as far as the potential participants are concerned, this is still only a dream. First of all, GIOVE-A, which was built by the UK company Surrey Space Technology Limited, has to demonstrate the reliability of its on-board high-precision rubidium atomic clock and the transmission of signals over two separate channels. The somewhat larger GIOVE-B, which is being built by Galileo Industries, a consortium whose members are Alcatel Space, Alenia Spazio, Astrium and Galileo Sistemas y Servicios, will carry a Hydrogen Maser clock as well and its signals will be transmitted over three channels simultaneously. This satellite will also be launched on board a Soyuz launch vehicle.

If testing of the two satellites and the ground segment goes according to plan, the first four operational Galileo spacecraft, already fitted with the equipment configuration of the eventual constellation of 30 satellites, will then be launched. These satellites are 2.7m x 1.1m x 1.2m in size and have a take-off weight of 700kg. Their solar panels span 13 metres and will generate 1,600 watts of on-board energy. Installation of the complete system should be completed by 2010.

From that point on nine operational satellites and one reserve will orbit the Earth on each of three different orbital planes and, in combination with the associated terrestrial control segment, will guarantee global coverage. It is expected that the system will be extended to incorporate regional and local components so that the signals can also be received at airports, in buildings or even in road tunnels with the aspired-to precision. When it comes to position fixing, this will mean an accuracy of ten metres in the global framework, four metres in the regional and one metre in the local framework, and this is guaranteed to every user.

Should the system malfunction, the user will be advised of this in less than six seconds, and at local level in less than one second. For position fixing and navigation purposes and also for time synchronisation, the open service will be offered free of charge and be capable of being received anywhere in the world. The main application is expected to be road traffic, while commercial services for surveying or fleet management will incur charges, but in return additional information from service providers will also be offered. On top of this there will be security-critical applications in road and rail transport, aviation and shipping, a public regulated service for national applications and a search and rescue service. All of this is to be implemented under a public-private partnership, with equal funding provided by EU and ESA.

From page 82 of FLUG REVUE 3/2006

Last updated 10 February 2006

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