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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.""
How about a cell phone jammer?
It is right here
Love them phrack DNS'.
suddenly I feel very tired
radio signals can be jammed?
Who'da thunk it?
Damn, next thing you'll tell me light can be blocked by opaque objects!
I suppose this device would be useful when hiring out from any US Car rental company, I don't know exactly which ones use the tracking though. Let's see how the "speeding" charges will be applied ;-)
Although I wonder how big the unit would have to be to be effective enough.. i.e. if it is as big as those old mobile phones (before the brick sized ones, more like a briefcase) then I doubt the average traveller would be bothered, but I suppose anyone who has come across any GPS tracking fines then they might like this quite a bit.
Just my $0.02
Are you local? There's nothing for you here!
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
Since, according to the GAO, in the last Gulf War, 80% of our "smart" bombs missed their targets, I don't think we'll notice if Saddam jams their guidance systems...
Military ordnance is not intended to WORK - it is intended to make profits for defense industry corporations who bribe Congress and the DOD for contracts...
After all, did we ever NEED 10,000 nuclear weapons? Of course not - we needed the MONEY we spent on them to insure our re-election...
Richard Steven Hack - This sig is TOO GODDAMN SHORT TO DO ANYTHING USEFUL WITH! MORONS!
From the Phrack text: "This device will have no effect on the precise positioning service (PPS) which is transmitted on the GPS L2 frequency of 1227.6 MHz and little effect on the P-code which is also carried on the L1 frequency. There may be a problem if your particular GPS receiver needs to acquire the P(Y)-code through the C/A-code before proper operation. This device will also not work against the new upcoming GPS L5 frequency of 1176.45 MHz or the Russian GLONASS or European Galileo systems. It can be adapted to jam the new civilian C/A-code signal which is going to also be transmitted on the GPS L2 frequency."
Also, there are other ways to deliver munitions. And there are other ways to jam munitions.
Man Gets 70mpg in Homemade Car-Made from a Mainframe Computer
More to the point, the Joint Program Office in charge of the GPS has known about cheap, readily available jammers since at least 1995. There's been an ongoing program since then called NAVWAR (NAVigation WARfare) researching ways to harden military GPS receivers against jamming
From the FAA's web site:
GPS is not yet approved as a sole means of IFR navigation. It can, however, be used as a supplemental system for en route navigation and nonprecision approaches.
Yes, FAA does certify GPS navagation systems, but it is ILLEGAL for a PILOT to use GPS as PRIMARY navigation. All the certification means is that it is legal to install the device into the aircraft.
How about (like an AC mentioned above) some HARMs? (High-Speed Anti-Radiation Missiles for you non-military-buffs). Nifty little missiles, designed to take out SAM sites, and enemy radar installations.
This is always a problem with active weapons systems, and active countermeasures... you broadcast your location to anybody who cares to listen. It's just like a HAM Radio foxhunt (that's an event where somebody plants a transmitter somewhere in a city, and a bunch of directional-antenna wielding HAMs try to find it). The military version just has slightly more lethal consequences for the "fox."
Jammers are great, until the high-explosive warheads start homing in on your signal.
Even if a man chops off your hand with a sword, you still have two nice, sharp bones to stick in his eyes.
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
"A real problem causer would then put it on schoolbusses filled with children. Or maybe in hospitals"
Under the LOAC, those civilian deaths are on the head of the military that planted the devices. The laws of armed combat prohibit the usage of humanitarian/hospital resources for any combat purpose... doing so makes those assets legitimate military targets. For instance, US combat troops are often made to check their rifles when they enter a hospital facility (even if it's a tent in the middle of the desert), to prevent a LOAC violation, and subsequent classification of the hospital/clinic as a military target.
When the israelis were taken to task recently for blowing up some terrorist leader in the west bank (which also killed the civilians he was hiding with), you had a perfect example of this. Those civilian deaths were the responsibility of the TERRORIST, since he chose to hide his legitimate-military-target self amongst innocents... the TERRORIST bears the responsibility for those lost lives. You will note, however, that you didn't hear the mainstream press blaming the palestinians.
If Iraq uses these jammers, there will certainly be civilian deaths. The world press, being totally ignorant of the realities and legalities of combat, will undoubtedly have a fit (in fact, Saddam is probably counting on it).
Of course, you can leave the jammer in place, and let an entire longstick of bombs fall aimlessly all over the city, killing thousands... or you can fire a single missile and take care of the problem. How many people do you think will magically "forget" to plug in their Saddam-issued jammers once this starts to happen?
If this turns your stomach, welcome to the club; I don't like the thought of innocents dying any more than anybody else. Hence, I think it's best to minimize that kind of thing by being as smart about it as possible. War is an ugly business... best to end it quickly.
Even if a man chops off your hand with a sword, you still have two nice, sharp bones to stick in his eyes.
In the last Gulf War, most of the precision ordinance was laser-guided. Lasers are very problematic because they are scattered by fog, mist, smoke, and dust. The GPS-guided munitions that are presumably going to be used in any upcoming war use radio signals that do not have this problem. Instead, it seems as though they will be jammed. The Small-Diameter Bomb project being pursued by Boeing is going to use a new GPS system that will be more robust against jamming.
Also, one can argue that thousands of warheads were necessary. The Russians had many, many warheads, too. Whoever lost superiority would be vulnerable to a first-strike that knocked out all missiles accurate enough to retaliate against armored silos.
A NYC lawyer blogs. http://www.chuangblog.com/