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Snooping Through Walls with Microwaves
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"
Aside from the fact that farmers and subsidies have all but shut down Alcoa in the US, Aluminum is a poor choice, and hence wouldn't be used. Lead. That would be the metal of choice. It has properties which make it excellent at sound proofing. Vibrating aluminum would modulate their signal quite nicely.
I don't think this a new technology. I think that this is just a new take on a technology that Léon Theremin (inventor of the Theremin instrument) was working on for the KGB in the 50-60s. He was using infrared bounced off of windows to detect conversations inside (or something). http://en.wikipedia.org/wiki/Léon_Theremin
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.
The summary mentioned microwave ovens, so some may be tempted to play around with a DIY radar. Don't!!! Of all domectic appliances a microwave is about the most dangerous to take apart. The RF radiation has a very high power and is invisible. When exposed to the electromagnetic field, currents start to flow inside the human body (mostly close to the skin) giving rise to burn-like wounds. Especially the risk of eye injury is significant. Don't try this at home.
The "Foil Room" won't help against snooping as you'd like to believe. (Prepare to ditch all your foil hats!!).
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 discussing similar topics.
-- dK
This has been around for a long time. In the book "Spycatcher" by ex-MI5 agent Peter Wright, he describes a bug used by the KGB to spy on the American ambassador in Hawaii (I think). There was a metal membrane hidden inside a wooden carving, which would passively vibrate with sounds in the room. A strong RF beam of around 900 MHz (details are hazy again, and it's not quite microwave) was directed towards the office from a fair distance away, then the signal would be minutely modulated and reflected by the metal membrane. It was able to work for several years, and this was in the 1960's. You can only guess what's available now.
There is no such thing as the English language. There are, however, at least two widely spoken dialects, both of which use different spellings for the word aluminium.
The Hacker's Guide To The Kernel: Don't panic()!
The element was discovered by an American who named it Aluminum. The British rejected this and gave it the name Aluminium for their usage (so it would end in "ium" just like HeliUM, LithIUM, BerrylIUM, etc). Aluminum is the standard American spelling. Aluminium is the standard spelling in British Commonwealth countries. While I appreciate the British desire for consistency, the Americans can legitimately argue that the person who discovered it should be able to name it whatever they bloody well want.
I say this as an Australian.
Here's a typical article about MIR. 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.org/features/doe/2004-09/dl
-- Real Stupidity is the Artificial Intelligence of the 21st century
A wodden copy of the Great Seal of the United States was bugged. Part of the seal was used as a diaphram and was used as a passive resonant reflector. This would pass most bug sweeps as the device was not active, but passive. When painted with a 330 Mhz signal, it would modulate it.
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
This bug is was delivered in 1946 and discovered in 1952.
The truth shall set you free!