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$30 GPS Jammer Can Wreak Havok
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."
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.
SJW: Someone who has run out of real oppression, and has to fake it.
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.
Never ascribe to malice that which can adequately be explained by tenure.
At Indy, all you need to know is "Turn Left"
rewriting history since 2109
messing with air-traffic controllers can get you some hard time. I think it's federal pound you in the ass time.
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?
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.
Atlas stands on the earth and carries the celestial sphere on his shoulders.
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.
0) Teaching women to use maps. "Gee honey, looks like the GPS satellites are down again. Now look here at this Atlas".
You must not be married.
I gave my wife a GPS so she can yell at it instead of me when she's lost.
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