http://rt.com/usa/news/texas-1000-us-government-906/ Dave

Hi Dave: The article shows a photo of a Predator, yet what the UoT guys did was hack a toy helicopter that used only the L1 civilian GPS signal. My guess is that they used a home made 3rd generation GPS simulator with a moderate power amp and antenna. http://www.prc68.com/I/5001A.html <- first generation single satellite single signal http://www.prc68.com/I/NTgpsSTR2760.shtml <- second generation multi satellite and multi signal Note that all GPS satellites transmit on the same frequency and so in a sense interfere with each other. But because of the orthogonally of the codes the receiver can process each signal. When a higher power signal is received the "capture" effect eliminates the weaker signals so a high power signal can easily "capture" the receiver. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html DaveH wrote: > http://rt.com/usa/news/texas-1000-us-government-906/ > > Dave > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > >

The picture is not of a Predator, it's a Global Hawk, a much larger aircraft. Didier KO4BB On Jun 28, 2012 11:47 AM, "Brooke Clarke" <brooke@pacific.net> wrote: > Hi Dave: > > The article shows a photo of a Predator, yet what the UoT guys did was > hack a toy helicopter that used only the L1 civilian GPS signal. > My guess is that they used a home made 3rd generation GPS simulator with a > moderate power amp and antenna. > http://www.prc68.com/I/5001A.**html <http://www.prc68.com/I/5001A.html><- first generation single satellite single signal > http://www.prc68.com/I/**NTgpsSTR2760.shtml<http://www.prc68.com/I/NTgpsSTR2760.shtml><- second generation multi satellite and multi signal > > Note that all GPS satellites transmit on the same frequency and so in a > sense interfere with each other. > But because of the orthogonally of the codes the receiver can process each > signal. > When a higher power signal is received the "capture" effect eliminates the > weaker signals so a high power signal can easily "capture" the receiver. > > Have Fun, > > Brooke Clarke > http://www.PRC68.com > http://www.**end2partygovernment.com/**2012Issues.html<http://www.end2partygovernment.com/2012Issues.html> > > DaveH wrote: > >> http://rt.com/usa/news/texas-**1000-us-government-906/<http://rt.com/usa/news/texas-1000-us-government-906/> >> Dave >> ______________________________**_________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/** >> mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> >> and follow the instructions there. >> >> >> > > > ______________________________**_________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/** > mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> > and follow the instructions there. >

And not the UAV of the story, I'm sure. -John ================= > The picture is not of a Predator, it's a Global Hawk, a much larger > aircraft. > > Didier KO4BB > On Jun 28, 2012 11:47 AM, "Brooke Clarke" <brooke@pacific.net> wrote: > >> Hi Dave: >> >> The article shows a photo of a Predator, yet what the UoT guys did was >> hack a toy helicopter that used only the L1 civilian GPS signal. >> My guess is that they used a home made 3rd generation GPS simulator with >> a >> moderate power amp and antenna. >> http://www.prc68.com/I/5001A.**html >> <http://www.prc68.com/I/5001A.html><- first generation single satellite >> single signal >> http://www.prc68.com/I/**NTgpsSTR2760.shtml<http://www.prc68.com/I/NTgpsSTR2760.shtml><- >> second generation multi satellite and multi signal >> >> Note that all GPS satellites transmit on the same frequency and so in a >> sense interfere with each other. >> But because of the orthogonally of the codes the receiver can process >> each >> signal. >> When a higher power signal is received the "capture" effect eliminates >> the >> weaker signals so a high power signal can easily "capture" the receiver. >> >> Have Fun, >> >> Brooke Clarke >> http://www.PRC68.com >> http://www.**end2partygovernment.com/**2012Issues.html<http://www.end2partygovernment.com/2012Issues.html> >> >> DaveH wrote: >> >>> http://rt.com/usa/news/texas-**1000-us-government-906/<http://rt.com/usa/news/texas-1000-us-government-906/> >>> Dave >>> ______________________________**_________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to https://www.febo.com/cgi-bin/** >>> mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> >>> and follow the instructions there. >>> >>> >>> >> >> >> ______________________________**_________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/** >> mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > >

I can't imagine that we don't sanity check without baro , altimeters . Isn't that the inspiration for the Kalman filter ?   --- On Thu, 6/28/12, J. Forster <jfor@quikus.com> wrote: From: J. Forster <jfor@quikus.com> Subject: Re: [time-nuts] Spoofing GPS - news article To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Date: Thursday, June 28, 2012, 9:53 AM And not the UAV of the story, I'm sure. -John ================= > The picture is not of a Predator, it's a Global Hawk, a much larger > aircraft. > > Didier KO4BB > On Jun 28, 2012 11:47 AM, "Brooke Clarke" <brooke@pacific.net> wrote: > >> Hi Dave: >> >> The article shows a photo of a Predator, yet what the UoT guys did was >> hack a toy helicopter that used only the L1 civilian GPS signal. >> My guess is that they used a home made 3rd generation GPS simulator with >> a >> moderate power amp and antenna. >> http://www.prc68.com/I/5001A.**html >> <http://www.prc68.com/I/5001A.html><- first generation single satellite >> single signal >> http://www.prc68.com/I/**NTgpsSTR2760.shtml<http://www.prc68.com/I/NTgpsSTR2760.shtml><- >> second generation multi satellite and multi signal >> >> Note that all GPS satellites transmit on the same frequency and so in a >> sense interfere with each other. >> But because of the orthogonally of the codes the receiver can process >> each >> signal. >> When a higher power signal is received the "capture" effect eliminates >> the >> weaker signals so a high power signal can easily "capture" the receiver. >> >> Have Fun, >> >> Brooke Clarke >> http://www.PRC68.com >> http://www.**end2partygovernment.com/**2012Issues.html<http://www.end2partygovernment.com/2012Issues.html> >> >> DaveH wrote: >> >>> http://rt.com/usa/news/texas-**1000-us-government-906/<http://rt.com/usa/news/texas-1000-us-government-906/> >>>  Dave >>> ______________________________**_________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to https://www.febo.com/cgi-bin/** >>> mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> >>> and follow the instructions there. >>> >>> >>> >> >> >> ______________________________**_________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/** >> mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.

Hi Steve: It's my understanding that they do have baro altimeters, gyros and accelerometers plus some other flight stability inputs. But . . . they seem to be vulnerable to some forms of GPS jamming or spoofing. If jamming started out with the same satellite positions as were currently in the sky then I don't see how the physical sensors would be of any help. It's similar to range gate walk off RADAR jamming. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html steve heidmann wrote: > I can't imagine that we don't sanity check without baro , altimeters . Isn't that the inspiration > for the Kalman filter ?