On 2010-02-09 10:52 , tosca005@umn.edu wrote:
Does the US government NOT have any plans to launch any more GPS satellites?
There will be more but of somewhat different design with better capabilities for terrestrial use. (Although potentially worse signals *above* the constellation, which is a concern for GPS receivers on HEO missions. I recall a presentation at the 2004 AMSAT Symposium on this. I'm not if this has changed.)
The last of the Block IIR-M satellites (8) were added to the constellation between 2005 and 2009. Those launched on Delta II vehicles.
There will be twelve follow-on satellites, known as the Block IIF series, and the first is planned to launch this year. They are being developed by Boeing and will launch on the Delta IV.
After that series, there will be more designated Block III with more advanced capabilities, although a contractor won't be selected until next year for these.
See http://en.wikipedia.org/wiki/GPS_satellite and http://en.wikipedia.org/wiki/GPS_modernization for good introductions.
73, -Daniel, VA3KKZ