Re: [Talk-us] [OSM-talk] Watch out if mapping in Florida, Georgia...
At 2011-01-21 08:15, SteveC wrote: GPS might not work; http://www.theregister.co.uk/2011/01/20/unavailabe_gps_warning/ Looks like this one extends as far north as SC, too. See other scheduled tests (in CA, FL, LA) here: http://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf -- Alan Mintz alan_mintz+...@earthlink.net ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] [OSM-talk] Watch out if mapping in Florida, Georgia...
Hello, Or it could be that they are testing their new satellites. The US has been working on deploying new generations of GPS satellites. Previously, you could get interesting ephemerides data from the satellite that was within 2 hours. Sometimes you could see 4 hours and now we have observed 6 hours ephemerides. There are a few changes coming in and I suspect this is just the new satellites test. I think it was number 5 or 25 that were changed recently. Emilie Laffray On 25 January 2011 08:52, Alan Mintz alan_mintz+...@earthlink.netalan_mintz%2b...@earthlink.net wrote: At 2011-01-21 08:15, SteveC wrote: GPS might not work; http://www.theregister.co.uk/2011/01/20/unavailabe_gps_warning/ Looks like this one extends as far north as SC, too. See other scheduled tests (in CA, FL, LA) here: http://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf -- Alan Mintz alan_mintz+...@earthlink.net ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] [OSM-talk] Watch out if mapping in Florida, Georgia...
On 21 January 2011 19:18, John Smith deltafoxtrot...@gmail.com wrote: On 22 January 2011 04:13, si...@mungewell.org wrote: Also if you know where the source of the jamming is coming from would it be possible to use that information to over come some of the degradation? Nope, not if the jamming is any good. Maybe they aim to find out. GPS-jammer-based global positioning system? :) According to [1] it is easy to detect and locate GPS jammers. Note that the news or the NOTAM doesn't actually say the signals are being jammed, but the decreasing radius with decrease of altitude suggests that... 1. http://en.wikipedia.org/wiki/Selective_Availability#Artificial_sources_of_interference Cheers ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] [OSM-talk] Watch out if mapping in Florida, Georgia...
At a guess, they are probably testing how well the system would work for the military if the signals were encrypted, as they probably would be in the event a terrorist group or foreign military were thought to be about to launch an attack using GPS-guided weapons. ---Original Email--- Subject :Re: [OSM-talk] Watch out if mapping in Florida, Georgia... From :mailto:si...@mungewell.org Date :Fri Jan 21 11:01:06 America/Chicago 2011 GPS might not work; http://www.theregister.co.uk/2011/01/20/unavailabe_gps_warning/ Similar NOTAMS issued for the west cost too Also https://www.notams.jcs.mil/dinsQueryWeb/displayGPSWAASNotamAction.do -- 01/019 (A0009/11) - GPS NAV GLOBAL POSITION SYSTEM PSEUDO RANDOM NOISE 25 U/S. 24 JAN 21:00 2011 UNTIL 25 JAN 09:00 2011. CREATED: 20 JAN 19:26 2011 -- It would be interesting to see what affect they can actually have a static receiver. I'll see if I can get some raw logs for this period. Simon. ___ talk mailing list t...@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk -- John F. Eldredge -- j...@jfeldredge.com Reserve your right to think, for even to think wrongly is better than not to think at all. -- Hypatia of Alexandria ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
