By 2008, Europe will be operating a constellation of 30 navigation satellites available to all users, everywhere. Called Galileo, it will provide free global positioning system (GPS) services to the public.
That's the plan but there's a way to go yet for full global integration. The USA operates the Navstar satellite system and Russia, Glonass. Galileo will join the worldwide system eventually.
The first European step will be called Egnos, which won¹t be a satellite system in itself but a GPS system overlay using existing satellites equipped with the required technology, says Claudio Mastracci, director of applications programmes at the European Space Agency. The main problem with GPS at present is that it is not totally accurate and a system is needed to improve it. Egnos uses geostationary satellites to relay extra information enabling users, including aircraft, to determine their positions with greater precision. Two Inmarsat 3 satellites and the Artemis spacecraft to be launched in July will be provided with an added GPS signal for accuracy improvement. This will create an initial system that will still cover a huge area. By 2003, Egnos "should be an operational system that can be dropped into the Galileo operation", Mastracci says.
Project
The Galileo project is funded 50/50 by ESA and the EU. It will kick off with a definition phase, provided it is given the green light by the ESA Council and the EU in November and December this year respectively. By 2005, three to four validation satellites will be launched to certify the system architecture and by 2008, the launch will begin of satellites to bring the Galileo system up to 30 operational craft. Sustaining the system with replacement spacecraft will require additional to be funding, says Mastracci.
Source: Flight Daily News