On 28 Mar, 2012, at 08:26 , David J Taylor wrote: >> Just wondering: >> >> 1) Is the UK govt doing this? > > The notice is from a UK Government agency. > >> 2) Is the USA doing anything similar? > > I would be surprised if they were not, but they may have more remote areas to > carry out such tests.
White Sands Missile Range, maybe. You can't fly over it, and a friend who lives in New Mexico and owns a plane tells me there is a standing warning for pilots flying around it to avoid relying on GPS for navigation. He has also heard of pilots doing that who have seen their position, as reported by GPS, suddenly shift by 50 miles. >> 3) What's the purpose? > > I understand that it's for the military to see how they would work without > GPS or on the event of GPS jamming. That sounds so unlikely. If they wanted to see what it was like without GPS they could just turn their GPS receivers off. More than this, a lot of your reports have them jamming the GPS L1 frequency alone and I don't think that would deny positioning to modern dual-frequency military GPS receivers. My guess would be that what they are practicing isn't jamming, which seems like it would require little practice, but rather is the much more high tech GPS spoofing, with the jamming being done to cover that up. Dennis Ferguson _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
