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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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  • 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.

  • Re:Vulnerable (Score:1, Informative)

    by Anonymous Coward on Tuesday March 08, 2011 @10:18AM (#35418324)

    Military has its own encrypted channels for GPS signals. Same satellites but not the same signal as consumer devices.

    However, all GPS guided ordnance will fall back to various other methods if the GPS fails (laser, optical, etc). For example, Tomahawk missiles also have an optical map following system. Most (if not all) GPS guided bombs will fall back to laser guidance if the GPS fails.

  • 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.

  • 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 codegen ( 103601 ) on Tuesday March 08, 2011 @10:34AM (#35418494) Journal
    If you bothered to read past the first page, you would have found out that the $30 box from the evil empire was shutting down Newark Airport twice a day because a truck driver was using it to defeat the toll transponder on the NJ Turnpike next door.
  • Re:ATM's??? (Score:4, Informative)

    by Ellis D. Tripp ( 755736 ) on Tuesday March 08, 2011 @10:37AM (#35418524) Homepage

    ATMs (and many other things) use GPS as a highly accurate master clock.

  • Re:WANT! (Score:5, Informative)

    by 0100010001010011 ( 652467 ) on Tuesday March 08, 2011 @10:40AM (#35418574)

    Deal Extreme has a few.
    High Power GPS Blocker with AC Adapter and Car Charger $26
    Mini GPS Blocker (with AC and Car Charger) - $105 []
    Super Mini Cigarette Lighter GPS Blocker - $80 []

    Or check out their full line of GPS and Cellphone blocking products. []

  • Re:WANT! (Score:3, Informative)

    by 0100010001010011 ( 652467 ) on Tuesday March 08, 2011 @10:46AM (#35418642)

    You could also build your own. The Wave Bubble [] is a *bit* fancier than those devices, but since it closes the loop on jamming frequency, you're almost guaranteed it'll be dead on.

  • Re:Vulnerable (Score:5, Informative)

    by Hydian ( 904114 ) on Tuesday March 08, 2011 @10:57AM (#35418776)

    Military has its own encrypted channels for GPS signals. Same satellites but not the same signal as consumer devices.

    While this is true, it just means that you need to jam a different frequency. Encryption has nothing to do with it as you aren't trying to access it, but DoS it. The reasons that the military runs its own separate GPS are for better accuracy (civilian GPS has inaccuracy built in while military GPS is accurate to within a meter) and so they can shut it down without hurting themselves within a theater.

  • 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 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.
  • Re:WANT! (Score:4, Informative)

    by DanTheStone ( 1212500 ) on Tuesday March 08, 2011 @12:14PM (#35419666)
    They continue to be extremely illegal. Tread softly.

Money can't buy love, but it improves your bargaining position. -- Christopher Marlowe