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Snooping Through Walls with Microwaves
Posted by
ScuttleMonkey
on Wed Oct 26, 2005 05:26 AM
from the time-to-buy-stock-in-tinfoil dept.
from the time-to-buy-stock-in-tinfoil dept.
denis-The-menace writes "According to an article from newscientist, scientists have devised a system to use microwave energy for surveillance. If people are speaking inside the room, any flimsy surface, such as clothing, will be vibrating. This modulates the radio beam reflected from the surface. Although the radio reflection that passes back through the wall is extremely faint, the kind of electronic extraction and signal cleaning tricks used by NASA to decode signals in space can be used to extract speech. Although, I doubt it would work in this room"
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1st sign the feds are onto you... (Score:5, Funny)
Re:1st sign the feds are onto you... (Score:5, Funny)
So the hell with eyes... it's actually possible to undress her with your diction...
Parent
OLD NEWS:This has been in active use since the 50s (Score:5, Interesting)
The second sign is when you feel toasty warm and the chair feels cold. In the 70's and 80's the carter and reagan administrations were perpetually complaining that the level of microwave energy measured inside the US embassy exceeded the OSHA limits for exposure. Eventually the US built a new embassy with enhanced shielding. UNfortunately the Soviet's put listening devices into the bricks. The embassy had to be knocked down and rebuilt. Of course, peter wright [bbc.co.uk] did exactly the same thing to the Soviet embassy in canada. Each night he snuck into the construction site and pulled wires up the inside of the walls to his microphones in specially made window sills. The soviet's learned about it from a mole in MI5 and had to build a second interior wall so that no rooms were near the windows.
Doppler microwave spying is quite old. As is laser vibrometry on windows.
Parent
Used Here (Score:4, Interesting)
-Waldo Jaquith
Parent
Re:OLD NEWS:This has been in active use since the (Score:4, Interesting)
The russians did that to the US, too. With a nice giant carving of the Great Seal - with a device behind a small hole beneath the beak.
Consisted of a cavity resonator about the size of a stack of 10 or so dimes, with a tuning post up the middle, a diaphragm for one end (to detune it according to air pressure) and a wire antenna maybe a foot long coupled into the cavity. Excite it with a microwave signal near but not dead-on the resonance and the reflection is amplitude modulated by the sound from the room.
Better yet: Put a diode in a movable surface. Excite it and it returns harmonics (easy to sort out from other reflections because they're on a different frequency), phase-modulated by doppler shift from the object's motion (like its variant FM, PM is very noise-resistant).
Russian laborers constructed an embassy where the walls were FULL of thousands of diodes - embedded in the construction material. US had to abandon the building and build one of their own. News items suggested the diodes were to make it hard to sniff for bugs. But IMHO they were the bugs themselves, using the harmonic-generation/doppler/PM trick.
Like the posting in the root article, this makes every surface a bug. You have to get diodes into them, but the return is cleaner and stronger than echoes from a passive reflector.
Parent
Re:OLD NEWS:This has been in active use since the (Score:3, Informative)
Oh, yes. They also did one on that pattern that was disguised as an olive-on-a-toothpick, to put in a martini glass and carry around or leave sitting about at embassy parties.
And the diode trick also turns anything with a diode in it into a bug.
Invest in AA (Score:5, Funny)
I think I'm going to buy stock in Alcoa Operations [alcoa.com]...with shenanigans like this going on, they can only increase in value.
In the meantime, here's some telltale signs you might be under microwave surveillance:
Watch for these signs and protect your privacy...cause the government certainly isn't going to.
Re:Invest in AA (Score:4, Informative)
Parent
Re:Invest in AA (Score:5, Informative)
Parent
Re:Invest in AA (Score:3, Informative)
I s
Re:Invest in AA (Score:3, Interesting)
Just Friggin' Great (Score:4, Funny)
oh no (Score:5, Funny)
Makes little difference (Score:5, Interesting)
The laser can be defeated by double glazing (I think), devices to vibrate windows and laser detectors (to tell you if you're being listened to).
A microwave device can be defeated by the good old tinfoil hat - by which I mean wallpapering in foil or otherwise turning the room into a faraday cage.
Re:Makes little difference (Score:4, Interesting)
hence, the drug lords of south america spend tonnes of tonnes of cash on goodies.
The best crims are never found out hence, their success and covertness.
a) buy gold
b) hide in 50% legit 5% return businesses
c) learn sign language
d) study tonnes of tonnes of history of cold ware espianage
e) never ever talk , paint a false picture to everyone including your wife/kids
f) cover tracks and never park anywhere, unless you own the govt, or they owe you billions.
Parent
Re:Makes little difference (Score:5, Funny)
a) buy gold
[..]
e) never ever talk , paint a false picture to everyone including your wife/kids
Doesn't that include not discussing it on Slashdot either? Plus, you forgot...
(g) Don't give away all your secrets.
Parent
Re:Makes little difference (Score:2)
A little bass will go a long way towards destroying whatever signal they think they can get.
Re:Makes little difference (Score:5, Funny)
Arrest them straight away!
Jolyon
Parent
Re:Makes little difference (Score:4, Funny)
Parent
Tin Foil Hat Designs (Score:3, Informative)
Re:Makes little difference (Score:5, Funny)
I'd suggest lining the walls with bags of popcorn. That way you'll know when you're under survellance and have a nice snack readily available.
Parent
In analogue phone days (Score:3, Interesting)
Just because the receiver was on the cradle didn't mean that the microphone wasn't active.
The cops played stuff back in interviews/court that was off topic but was the occupants bitching about each other to try and divide and conquer them.
This was in Leeds, UK.
I can't remember many more details or find a link. I didn't know them at the time and only heard about it later as a warning.
Re:In analogue phone days (Score:3, Informative)
Re:In analogue phone days (Score:5, Funny)
Evidence?? Court?? You are running an old version of UK, please upgrade where these bugs have been removed in an effort to improve security.
Parent
Re:In analogue phone days (Score:5, Interesting)
Survellience was also carried out against embassy cypher machines using unshielded telephone cables picking up eletromagnetic emissions from the cypher machines, in many cases enabling the reading of both the en clair message and the cypher material.
None of this was admissable in a UK court. Phone tap evidence still isnt.
Parent
Not new tech (Score:4, Informative)
Fluff piece (Score:5, Informative)
Even at 100GHz, the wavelength of microwaves is 3 mm. But sound waves inside a room would cause a surface to vibrate perhaps 0.001 mm. You cant modulate a 3mm wave to record 0.001 mm changes.
Re:Fluff piece (Score:2)
Yes. The last time I heard this story, I thought they were using a laser beam -- which makes a lot more sense.
Re:Fluff piece (Score:5, Interesting)
There's an anecdote in the engineering field: where some poor sods at Racal-Dana had a phase detector at 50MHz that was so sensitive to vibration they had to stop their experiments whenever a plane took off from Orange County Airport (quite a few miles away). They eventually had to get special thick aluminum wall castings to enclose the phase detector to block the vibrations. And this was at just 50MHz. Phase detectors get more sensitive proportional to operating frequency, so a 5,000 MHz phase detector is *mighty* sensitive!
Parent
Re:Fluff piece (Score:5, Insightful)
Interference detectors, more commonly known as interferometers, can detect distances far below the wavelength used to make the measurements. For example, 800 nm infrared laser light can readily be used to resolve 5 nm differences (I've worked on the development of such a system). Further, the distances being considered for measuring the movement of things like clothing or the throat and chest of the speaker are far above one micron (0.001 mm): put your finger on your throat and speak; think that's one micron you're feeling?
Parent
It was news... 45 years ago. (Score:4, Insightful)
Re:It was news... 45 years ago. (Score:2)
Re:It was news... 45 years ago. (Score:5, Interesting)
- There were no "lasers" in 1960. At least not the very stable continuous-wave lasers that you need for this, and especially not in the USSR.
- Think-- do lasers go through glass? Do lasers bounce off glass? Might other wavelengths of electromagnetic radiation act similarly?
- Microwaves bounce off most anything, if you pick the right angle. Conveniently, most buildings have the windows recessed a bit, and any concave corner makes an EXCELLENT "corner reflector", which has the amazing property of bouncing any incident beam right back to the sender.
Not only did they bounce microwaves off glass-- they had the hutzpah to give the US ambassador a honorary plaque, which he hung on his office wall. Unbeknownst to us, there was a little diaphragm inside the plaque, just the right wavelength to reflect K-band microwavesm, which vibrated very nicely to every word spoken in his office. Look it up.Parent
Re:It was news... 45 years ago. (Score:3, Interesting)
I looked it up. 330 MHZ is not K-Band microwaves. It's UHF. HF is from 3-30Mhz VHF is from 30-300...
The bugged seal had a resonant quarterwave antenna tuned to 330
How long? (Score:3, Funny)
Food fun (Score:4, Funny)
This isnt new (Score:3, Interesting)
If you look at any high security building(NSA, etc) they will have multi layers on the outside and inside of the buildings.
Not only is it physical security, but sound and wireless security.
foil vibrates too (Score:2, Insightful)
Re:foil vibrates too (Score:3, Funny)
Let 'em try then!
Microwave Eavesdropping (Score:2, Funny)
Very dangerous!!! (Score:4, Informative)
I can see the RIAA using it!! (Score:3, Funny)
Tinfoil hats (Score:3, Insightful)
*Sigh* what now?
J.
Foil Room fallacy (Score:3, Informative)
To truly block signals, you'd need to build a actual Faraday "cage" built with the smallest possible 'holes' so the waves created inside (be it voice, the sound of you typing or even waves emitted by the blinking LED from your Ethernet card) will be cancelled out. This is the same technology that the intelligence agencies employ against counter intelligence. That with foil (which is properly grounded) will work.
Solid surfaces such as foil can actually act as large AMPLIFIERS if implemented incorrectly since the waves will
Note that your microwave is surrounded by a Faraday cage to protect you from the rays; not foil.
A quick Google to back up my post yielded this page [montalk.net] discussing similar topics.
Not quite microwave (Score:4, Informative)
Electronic signal cleaning technhiques (Score:3, Informative)
That being said it is easily defeated. For example - short wavelengths below 1cm start resonating with water vapor. That's why doppler radar has been such a boon to meteorology.
But there are ways to stop it. Metal impregnated and grounded cement walls that are, oh, 6 to 8 feet below grade level would be reasonably safe. Of course don't put any windows, just ventilation.
And if you're really that much of a target they'd bug the place before they resorted to using microwave to listen in. BTW, for a good fantasy view of using microwave to peek in I highly recommend watching "The Siege" with Denzel Washinton and Tony Shaloub.
Old news (Score:4, Informative)
The only update in the article is now they use microwaves and common materials already in a room.
Details here;
http://www.spybusters.com/Great_Seal_Bug.html [spybusters.com]
This bug is was delivered in 1946 and discovered in 1952.
Re:Coral Cache sucks (Score:3, Insightful)
When that happens, NO ONE can get to the page, not just those with lame firewalls.
[ObNerd]
The needs of the many outweigh the needs of the few.
Re:Tinfoil hats out, team! (Score:3, Interesting)
Microwave Impulse Radar / Ultra Wideband Radar (Score:3, Informative)
Here's a typical article about MIR [llnl.gov]. Last I read, there were legal battles about shoddy treatment of potential vendors by the LLNL. Slashdot readers would probably do well to track this technology!
A taste of this from http://www.eurekalert [eurekalert.org]