GPS Satellite 2F-1, the first of the new generation, of GPS satellites launched May 28 after several delays after the program was announced in 1996. The 2F is designed to replace to Block 2A satellites which were launched 1990 and 1997 and were supposed to have a 7.5 year life span. 11 of those satellites are still used in the GPS constellation (4 of which were launched in 1992 or before). It is part of an $8 billion upgrade of the system which will take more than 10 years.
Among the advantages of the new satellites:
*Doubling in the predicted signal accuracy (the new generation of satellites is supposed to increase the accuracy from 20 feet to 2 feet)
*Variable power levels for the military to boost performance
*Better resistance to jamming
*12-15 year design life
* Reprogrammable processors
*Atomic cesium digital clocks (the earlier versions were analog)
*No “Selective Availability” hardware (hardware which made the satellites deliberately less accurate for civilian use – a feature which was turned in 1996)
The Russian GLONASS satellites which will provide GPS coverage are scheduled for launch in August and the European Galileo System is targets for 2014. Speculation has been that properly configured hardware could use the various systems for even more accuracy.