GPS is not the only global navigation satellite system out there, at least not for long. There are other nations trying to break their dependence from USA’s globally available free service – which can be shut down at will of U.S. military. Not to mention GPS (Navstar) is aging (even older than 1st generation iPods!!!) fast and it needs some serious upgrading.
European Union – Galileo
Initiated in 1999, Galileo is a joint effort of European countries. When first started, the U.S. opposed the plans stating that it would end their ability to control positioning satellites in military conflict scenarios. The pressure from the U.S. backfired and as a result the Galileo project was over-funded by European nations who decided it was crucial to be independent of U.S. controlled GPS.
The total cost of the system is expected to be around €3 billions. Galileo is funded by EU nations and China.
Primarily intended for civilians, Galileo will support different kinds of services: OS (open service) will broadcast in two bands (1164–1214 MHz and at 1563–1591 MHz) and when both are used you’ll be able to get <4 meter accuracy. CS (commercial service) will require a fee but if used with ground stations it will be able provide accuracy of less than 10 cm’s. It will use an extra band at 1260–1300 MHz in addition to the OS frequencies.
Number of satellites: 30
Completion Date: 2011
Current Status: First satellite launched in December 2005 and first ‘Galileo’ signal received in January 2006.
China – Beidou
China’s Beidou was first planned to be used for military purposes but Chinese government has already announced it will be free for civilians as well. This would conflict with EU’s Galileo which plans to profit from selling of receivers and subscriptions to benefit from high accuracy signals.
Russia’s Glonass has a long history which goes as far back as the peak of Cold War. The Glonass system has never been globally available since then, mostly due to instability in Soviet Union and current Russia. India, and possibly China, collaborate with Russia on Glonass. Since 1992 Russia has launched 44 satellites, some of which are no longer in service. Glonass’ civilian signal – which is only available half the time in Russia, and less globally – can provide <100 meters of accuracy. Military signals are better, providing accuracy of <15 meters. Russia has announced that it would make military grade signals available this year.
Completion Date: Coverage of China and neighbors by 2008 – global coverage in later years
Number of satellites: 35
Current Status: 4 satellites in orbit
Russia – Glonass
Completion Date: 2011
Number of satellites: 24
Current Status: 16 in orbit, 5 of which is switched off. 12 more scheduled to be in orbit in the next two years
India – IRNSS
Indian Regional Navigation Satellite System, IRNSS, was recently approved with a budget just over $300 million. IRNSS is planned to provide only regional coverage provided by 7 satellites.
Number of satellites: 7
Completion Date: 2011
Current Status: First satellite to be launched in 2008
USA – Navstar (GPS)
It is the only fully functional, globally available navigation satellite system so far. It is free for everybody on this planet. The first one of the satellites was launched in 1978 and the system has been fully operational since 1995. However the satellites get old and need to be replaced and technological advancements require GPS to be upgraded.
The modernization has been approved since 2000 and is called GPS III. The new system will provide capabilities such as to shut off GPS service to a limited geographical location while providing GPS to US forces. The new GPS III satellites will still provide legacy capabilities while adding high-powered, anti-jam military-code signals.
These satellites will have about 500 times the transmitter power of the current system, multiplying its resistance to jamming. With a constellation of 30-32 satellites, GPS III will have second and third frequencies to contain civilian signal, L2 & L5, more robust signal transmissions, and provide real-time unaugmented 1 meter accuracy.
Completion Date: 2011
Number of satellites: 24+
Current Status: Fully functional, upgrade in process.
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