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$30 GPS Jammer Can Wreak Havok 386

An anonymous reader writes "A simple $30 GPS jammer made in China can ruin your day. It doesn't just affect your car's navigation — ATM machines, cell phone towers, plane, boat, train navigation systems all depend upon GPS signals that are easily blocked. These devices fail badly — with no redundancy. These jammers can be used to defeat vehicle tracking products — but end up causing a moving cloud of chaos. The next wave of anti-GPS devices include GPS spoofers to trick or confuse nearby devices."
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$30 GPS Jammer Can Wreak Havok

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  • Redundant (Score:2, Funny)

    by nenya ( 557317 )
    Such a device already exists. It's called "Indianapolis." I swear, I can never get good GPS signal in that damn town.
  • a device jamming technology X doesnt just disturb one type of device dependent on that technology, no, it jams ALL devices depending on X

    News at eleven..

  • by elrous0 ( 869638 ) * on Tuesday March 08, 2011 @10:12AM (#35418244)

    What's even more disturbing is that the FAA is currently looking to move away [] from traditional radar and even human air traffic controllers [], as part of their "NextGen" system []. GPS is just fine as long as there is a redundancy in the system. But the idea of abandoning radar as if GPS were a time-tested system is a little scary.

    • by ScrewMaster ( 602015 ) * on Tuesday March 08, 2011 @10:44AM (#35418620)

      But the idea of abandoning radar as if GPS were a time-tested system is a little scary.

      It is time tested. It works very well. It's just more vulnerable.

    • I wonder how this would affect a plane landing if somebody set one off while flying on a plane right before touch down. Anybody know? Would the plane automatically abort? Would the pilot have enough time to manually take over? Would it crash?
      • by colinnwn ( 677715 ) on Tuesday March 08, 2011 @11:10AM (#35418902)
        It would affect nothing. Pilots have a "decision height" at which point they must go around if they can't see the runway. GPS, along with several other technologies, allows 2 things, a lower decision height, and automated landings. Rules that regulate pilots and avionics require that the pilot is always able to identify a failure, and to be reasonably able to safely recover from a failure using alternative instruments or procedures. If the plane's GPS were to loose a fix, it would set off an alarm, and the pilot would either immediately start a go-around, or s/he would choose to land manually.

        Planes also have an IRU (internal reference unit) or laser gyroscope that is able to dead reckon where the plane is based on the fact of knowing where an aircraft was at some previous point, and summing up all of the movements of the aircraft since that point. Before GPS, using IRUs were the primary automated navigation tool for commercial aircraft. So even in the event of a loss of GPS fix, the aircraft still knows exactly where it is for a long period of time. I don't know if the IRU can feed its location fix back into the NextGen aircraft transponder (which normally uses GPS) that reports to air traffic control computers where the aircraft is.
      • by sznupi ( 719324 )
        Autoland (or, more generally, glide slope guiding) systems aren't build around GPS.
    • by kaiser423 ( 828989 ) on Tuesday March 08, 2011 @11:05AM (#35418870)
      Modern INS is good enough that even if you lose GPS lock, you'll be able to get where you're going very precisely. You can dead reckon very, very well with modern equipment.

      I was recently flying a fairly expensive INS, and broke GPS lock in the middle of a flight. 3 hours of jet flight later, that INS showed me on the runway with the same 6-DOF (position, yaw, pitch, roll) within a couple of meters of what a still locked system was doing.
  • by dtmos ( 447842 ) * on Tuesday March 08, 2011 @10:12AM (#35418256)

    $30 GPS Jammer Can Wreak Havok[sic]

    (Technical): ...which is why they are illegal in nearly every regulatory environment.

    (Snide): Gee, I didn't realize a GPS jammer could break an Intel SDK []! Oh -- you meant havoc?

    • by Joe U ( 443617 ) on Tuesday March 08, 2011 @10:19AM (#35418332) Homepage Journal

      (Technical): ...which is why they are illegal in nearly every regulatory environment.

      Like drugs and guns, which we now have none of.

  • Old news (Score:5, Interesting)

    by GPSguy ( 62002 ) on Tuesday March 08, 2011 @10:15AM (#35418286) Homepage

    The ability to white-noise (or pink-noise) jam GPS has been around and employed for, literally, years. And, most of the first of these I saw came from China, too. GPS is a relatively fragile system, at least n the L1-C/A world: GPS satellites have limited power budgets so signal levels are low on the ground. Receivers have high gain. Multipath in urban environments can confuse receivers. Emitting a random noise signal over the range of L1 frequencies isn't that hard, and doesn't take much power... or antenna height... to cause problems.

    The article makes all of these points. Read it and take note of the fragility of the system. That's its downfall, not a $30 device.

  • by Joe The Dragon ( 967727 ) on Tuesday March 08, 2011 @10:15AM (#35418298)

    messing with air-traffic controllers can get you some hard time. I think it's federal pound you in the ass time.

    • by Lumpy ( 12016 )

      If you really want to mess with ATC, you can do it far easier than a $30.00 short range jammer.

      Go to hobby shop, buy a few large model rockets. build them.

      Go to grocery store, buy a roll of aluminum foil.

      feed aluminum foil into a crosscut paper shredder to create "chaff". (I can tell you how to do this successfully, but wont to keep the complete idiots from trying it.)

      Load the chaff into the ejection chute tube for the model rockets. (again, there is more to this, but idiots will never figure this step ou

  • they can be used to trick china and great britain to the brink of war by fooling the royal navy into invading chinese waters. then a stealth boat can make the other side think someone is shooting missiles at them. all of course, so rupert murdoch, i mean, uh, elliot carver, can sell... newspapers!

  • The article just highlights why radio/microwave interference is taken so seriously by authorities. The fact a jammer costs $30 is moot, buying a jammer is illegal and stupid.

    How much gunpowder could you buy for $30 (or just raw ingredients for bombs)?
    • How can it be illegal if a single 4G WiFi device blocks GPS [] in a radius of several kilometers?

      • And how can drugs be illegal if there's a guy that sells them in the local park. Just because they're out there doesn't change the legality. In this case the testing hasn't been completed, most likely it either doesn't have that impact or the devices will be yanked. The FCC doesn't allow devices to interfere in that way, so I'm guessing that somebody screwed up in evaluating them.

  • Oh, bad form... (Score:5, Informative)

    by fuzzyfuzzyfungus ( 1223518 ) on Tuesday March 08, 2011 @10:26AM (#35418418) Journal
    I'm not surprised by how many devices would use GPS(the ability to get a fairly accurate location fix and a damn accurate timebase for peanuts and an OK view of the sky is certainly attractive...); but I am surprised, a bit, at how many "serious" systems(even ones where hostile action is to be expected, like ATMs, or where failure Just Isn't Acceptable, like air traffic control) wouldn't have some degree of redundancy, if only because of the risk of a cheap GPS module burning some sensitive RF chip because the local arc-welder user fired up again...

    Your basic RTC, say, isn't as accurate as GPS time; especially in the long term, or if not temperature compensated and subject to variable conditions; but it should still deviate by less than a second over a day or two of lost GPS(never mind 10-60 minutes of jamming) and can, if needed, retain reasonably accurate time for as long as power holds out, and they don't need much power.

    Similarly, today's MEMS accelerometers and on-chip magnetometers/compasses, while you might not want to dead-reckon your way around the world with them, can easily enough compensate for losses in GPS fix over the short term, and can 'sanity-check' abrupt changes in GPS readings.

    For static objects(like radar towers) you can basically treat position as a constant(possibly with recalibration from time to time if there are structural shifts) and calculate dish position based on a simple rotary encoder or the like.

    Obviously, for space, power, and cost reasons, Joe Consumer's $50 cellphone or $80 dash-nav isn't necessarily going to incorporate multiple layers of GPS failsafe. If the GPS stops working, Joe can just use the meat-coprocessor he stores in his skull to suck it up and figure it out until GPS comes back online.

    For more important systems, though, I would honestly have hoped for better, especially in situations(like cell towers and most ATMs) where the equipment itself isn't exactly inexpensive, so $50 or $100 worth of accelerometer and RTC failsafe would be reasonable, and where they usually have a network hard-line. NTP isn't perfect; but it certainly is handy(if necessary, users of dedicated circuits, rather than those who rely on public internet, might be able to achieve even greater accuracy by comparing their GPS time with the GPS time reported by the hardware on the other end of the circuit, to determine the round-trip time fairly exactly...)

    Also, the "backup" gyrocompass mentioned in TFA, that failed to act as a backup to GPS because it crashed when it lost GPS signal is just sad. Perhaps it was purchased from the same company who provides emergency generators that can only be started by mains-powered control systems?
  • by Anonymous Coward

    Finland has had plans to introduce a road toll system based on GPS. If that happens, spoofing/jamming GPS will save you a lot of money. As a side-effect of everyone using blocking devices, nobody will be able to navigate anymore :)

  • by oneiros27 ( 46144 ) on Tuesday March 08, 2011 @10:46AM (#35418634) Homepage

    People forgot about it due to the ong solar minimum, but if this many things are dependant upon GPS, they're going to want to find some contingency plans:

  • by bradley13 ( 1118935 ) on Tuesday March 08, 2011 @10:51AM (#35418702) Homepage

    What competent engineer would design an important system that depends on GPS, with no backup? The satellite signals are very faint, and can be disrupted for seconds or hours by lots of different causes, including entirely natural causes like solar flares.

It seems intuitively obvious to me, which means that it might be wrong. -- Chris Torek