At 8:58 PM 8/16/96, Alan Horowitz wrote:
TIm, a layer of tin foil is not the same as a professionally installed and maintained Faraday cage.
I can envision circulating currents on the tinfoil. Ie, ground loop type of situation.
All imaging is depenmdant upon the target having some radiating characteristic. If the gun shields a gun-shaped peice of the body from radiating in millimeter waves, you can build a gun detector.
There's no other way to say this: you simply don't know what you're talking about. Your protestations to the contrary, reconstruction of an image from point sources of leakage is essentially impossible ("the phase problem"). Analyze the solutions for sources behind screens. (A simple model is to analyze the radiation patterns one one side of conducting plate, with various sources on the other side.) For an intuitively visualizable model, consider a pattern of some sort (like a gun) behind a screen, with light leaking around the edges. (The less light leaks, the more the example is similar to the case of deliberate shielding of RF sources, but even the simple example here makes the point.) This is what crystallographers and DNA analysts call "the phase problem." Spatial frequency (pattern) information is indeterminate. If you still believe what you say, that a gun can be imaged even when behind a conducting screen, based solely on leakage around the edges (or similar small leaks), I challenge you to produce a paper which demonstrates this, or, even better, an actual demonstration. --Tim May Boycott "Big Brother Inside" software! We got computers, we're tapping phone lines, we know that that ain't allowed. ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay@got.net 408-728-0152 | anonymous networks, digital pseudonyms, zero W.A.S.T.E.: Corralitos, CA | knowledge, reputations, information markets, Licensed Ontologist | black markets, collapse of governments. "National borders aren't even speed bumps on the information superhighway."