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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.
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.
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