On Thu, Jan 20, 2011 at 5:25 PM, <[email protected]> wrote: > Another time I was driving I-5 near Lemoore Navy airstation and got a > different type of jamming. The whole gps display rotate back and forth. No > idea how that jamming was done.
Not just with GPS but in general that is the more sophisticated and useful method of jamming. Think of an airplane being targeted by an radar guided missile. It could simply broadcast while noise but then it would become a very bright target to a radio homing missile. And you can bet $$$ that all radar guided missiles have a radio homing mode build into their software. The smarter jammer sends a faulse signal back that is only "off" enough to cause the missile to miss but not "off" enough that the missile can know it is being jammed. A smart GPS jammer would slowly "move" the location reported by any GPS receiver in the area just enough that weapons would miss their targets Your civilian GPS can't really know if it is hearing a satellite or a nearby 1.5GHz transmitter and will just take the stronger signal The military GPS units are much harder to jam because they listen to an encrypted signal. So a military jammer either has to have the right key (very unlikely) or just blast out white noise and make himself a very bright target for radio homing missiles. Jamming is a very sophisticated science because for every trick there is are counter measures and so on for several layers -- ===== Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
