Researcher messes up Wi-Fi with an rPi and bargain buy radio stick KU Leuven Phd student Mathy Vanhoef has smashed conventional wireless security thought by creating continual, targeted and virtually indefensible stealth jamming of WiFi, Bluetooth, and Zigbee networks, and tampering with encrypted traffic, with little more than a $15 dongle. The wireless security boffin presented his work at …
One of my old wifi cards (PCI), the sucker would lock up every so often.. with the transmitter jammed on. I don't know if it was transmitting the same packet or jibberish, or just whatever the equivalent of an empty carrier is for OFDM, but the whole network would drop dead until I powered off the computer (rebooting the computer would not reset the card.)
The BT hopping is only in the 2.4Ghz ISM band (11 chs USA, 13 Chs in Europe). Old 11Mbps WiFi used one channel. 54M bps uses 3 to 4 channels. The fastest modes use all the channels. So it's possible to degrade BT, except there is the inverse square law, most BT applications are 10cm to 100cm distance link.
A transmitter amp would be illegal in EU and USA. But certainly without an amp, WiFi in the same premises will crawl. Add another posher stick and you can jam the other 5.8Ghz WiFi band.
Jammers are illegal in most countries, even if done with an off the shelf stick.
When I specced my Galileo, I intentionally picked up the Intel dual-band, 2x2 MIMO with 6dB gain on the antennae. Not for the jamming capability but for higher throughput. It does Bluetooth as well. And cost more than the Galileo. And... it can be swapped in on the three laptops should the need arise.
This actually looks interesting. A mobile, ground-based drone with an EW suite. Sweet!
One would hope that a decent alarm system had been designed such that, if it did not receive valid 'still alive' signals from sensors on a regular basis, it set off the alarm. Otherwise it would be at risk from having signals blocked or having the sensors removed.
Friedland response alarms have a setting for this. But it's not on by default and the manual states it's not a great idea as it can cause false alarms.
I also wonder what happens with the wireless siren - it may well not go off and leave you relying on the one built into the main panel.
Who needs a jammer? Once went to a dealer to collect a brand new car only to discover that he couldn't open the doors properly. Whatever he did, only the driver's door would unlock and the others had to be opened using the switch inside.
We took the car home anyway and (as is my fetish) RTFM to discover that for that model of car - and it seems uniquely for that model in the manufacturer's lineup - unlocking all the doors required a long press of the button. A short press would just do the driver's.
Older models by the same manufacturer unlocked all doors on a short press, and newer models required two presses in fairly quick succession with the first doing the driver's door, the second everything else.
Mind you, we'd already fairly lost confidence in that dealer as, sitting down and signing the paperwork, we glanced out of the window to find that their mechanic was screwing the wrong numberplates onto our car.
M.
The magnetron is the kazoo of radio transmitters. You do not try to tune it delicately for a precise output - you calibrate it for more-or-less what you want and make do with the very broad spectrum it puts out, hopefully centered roughly where you want. They also operate at very high power, and depend upon the screening of the microwave oven to hold the field where it belongs - so the slightest imperfection in containment turns it into a wide-spectrum 2.4GHz jammer.
Use a legit 2.4GHz videosender bought off the shelf. These things (used to) operate by modulating the video and audio onto a continuous carrier somewhere in the 2.4GHz band and could happily cause enough disruption to wifi etc (perfectly innocently) to render them unusable, even if not completely jammed.
The one in the article's certainly more interesting than a videosender-as-jammer and probably more reliable too.
ps
wireless car key systems typically operate around 433MHz in Europe so a 2.4GHz jammer doesn't do the magick.
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