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GPS Jamming for $50
Anonymous writes "One of the newest hacker tools out there is a homemade GPS jammer. According to this article in Computerworld, such jammers can be built with $50 worth of electrical parts. Phrack has published a how-to aimed at inexpensive GPS-based navigation and "hidden tracking devices.""
It is right here
Love them phrack DNS'.
suddenly I feel very tired
Jammers can be defeated or made substantially less useful using beamforming. I would be stunned to find out that military users are not doing so.
If a beamforming receiver gets its position and orientation (yaw, pitch, roll), at any point in time, it can steer the sensitivity vectors of its antenna pattern to minimize the effect of jammers from then on. More sophisticated systems will probably also steer nulls right at the jammers.
I really don't understand what the fuss is all about. The military has surely had this technology for ages, along with every thinkable agency and "enemy". It's just a normal radio frequency jammer, one in the long line of other technical warfare devices, like radio jammers and EMP guns to wipe out magnetical data or stop a car. It doesn't take an electrical engineer to invent one (well, actually, it does :).
All organizations have this technology, but it's only when it falls in the hand of the "stupid" (uncontrolled/uncontrollable) individual that these organizations start making noise.
It is explicitely illegal for pilots to rely on GPS for navigation. Of the several types of navigation you learn when you earn your pilots license, GPS is not one of them. Even if a (assumed general aviation) pilot was breaking the rules and relying solely on GPS for navigation, its not like the GPS begin jammed would suddenly screw him. He can always go back to the more reliable methods, including the tried and true "looking out the window".
:P
To be effective, GPS jamming would have to have a range of at least 20 miles, which would be a signal that would be quite easy to track down and stop.
Who else uses jamming? The military can use it, but again, its not like jamming is going to do much because missles can be targeted at the jammers.
Hikers could be screwed I suppose, but few hikers rely on GPS for their lives.
GPS Lo-Jacks could be disabled, but activating a GPS jammer would be like turning on a huge beacon pointing straight to the thief anyway.
Street-map GPSs could be disabled, but given their accuracy, most people wouldnt even notice
I am so sick of hearing about the benefits of cell phone jammers, I just had to respond to this.
What if they were legal? You could bring one to the movie theater, whee! Would you be happy? Perhaps, but only until you'd discover that someone thinks talking on the street is impolite. Or notice that a customer of your favorite bar doesn't like them.
If jammers were used commonly, the only place you'd be able to make calls without the fear of jamming would be from within your own home. Which kinda defeats their whole purpose, doesn't it?
Jammers are evil. Period.
Not to mention what I think of limiting the options of polite moviegoers just to deter impolite people. It is analogous to what the RIAA is doing to honest customers in order to fight piracy, and no one here seems to agree with that. Hypocrites...
My Sig: SEGV
There are minimal benefits (none come immediately to mind) but the fact is they would land you in a world of litigation. Who wants to be sued by everyone who couldn't get thru to emergency services on their cell phone for the entire period they owned a cell jammer. Cause they would, and the shitty court system here in America would find in their favor cause you couldn't prove you never used it. And that's after you've been found guilty of negligent manslaughter in those same cases for the same reason. IANAL, but this is what i would imagine happening. If the feds didn't decide to take you away as a terrorist, cause only terrorists would want to use jamming technology (for those of you who can't see it, that was sarcasm in that last line)
any radio signal can be jammed. GPS signals are especially easy to jam because the satelites are 10 thousand miles away and have low power transmitters to begin with since electricity in space is precious.
:)
How big does the device need to be? Not very big. No bigger than a typical GPS receiver. What's FAR more important is the size of your antenna. A nice parabolic dish (say, an old DSS dish) with 24db gain could probably be used to jam a GPS receiver from a mile away while running very low power. A lower gain antenna could be just as effective if the power were higher, though, and would be less directional to boot. They pack 100 watt transmitters into a case the size of a car stereo these days, so the device definately doesn't NEED to be very big.
Of course that's assuming you want to block from a good distance, if you are within about 10 feet of the GPS receiver, you can probably jam it with a few miliwatts of power and a wet piece of string for an antenna. You could make a GPS jamming PC card, or SD card even. Oh wait SD is a stupid closed standard. But a low power unit could be easily be made small enough to, say, jam up your ass.
This isn't new, or revolutionary, or even news worthy. Electronic warfare has been around as long as electronics and the bad guys are always trying to jam the good guys comms and vice versa. Ever since that bozo went on the news and talked about this everyone's had their panties in a bunch. Iraq could probably shit out a couple of ghetto GPS jammers but I doubt if they have the resources to produce the 10,000 units they'd need to really make a measureable difference in the outcome of the war. Oh and by the way we can play the same game by using directional antennas on our receivers to reject jamming signals.
And one final note, anything that emits an RF signal is easily locateable. See radio direction finding, ham radio fox hunts, etc. Shit, our forces could just home in on the jamming signal
-73, de n1ywb
www.n1ywb.com