🚀 go-pugleaf

pretty-boy@cup.portal.com says:
>A simple way to eliminate radar detection is to just xmit a signal
>that obliterates that of your fascist opressor [ :-) ] ...
>The TRICK is fiting with FCC about the under 100mW rule ... 

Just as a technical exercise, mind you, it occurs to me that *the*
maximum sizzleage at the least possible power would be achieved
using a "phase conjugate active mirror" (see Sci. Amer. Dec '86 and
also Jan '87; I also have a ton of other research references if anyone
wants more). You need two horizontal masers that form a standing
wave in a nonlinear material (nonlinear in terms of an acoustical
response in the microwave region of interest; the acoustical waves
match the maser standing wave pattern to form a diffraction grating).

Into this material you get the radar beam from the cops. By interaction
with the standing wave diffraction grating you form a virtual image
(the complex conjugate of the incoming object wave pattern). There's
a real image too, but you ignore that. Then you amplify the holy
s**t out of the virtual image (you know, a maser amplifier rather than
an oscillator), and the resulting return beam is 100% directed back
at the image of the original transmitter, with effectively no loss.
It is furthermore perfectly phase-matched to the resonant frequency
of the transmitter, regardless of any passive distorting mediums along
the beam path (e.g. reflection from a metal shed alongside the road),
resulting in maximum efficiency of absorption.

This kind of stuff is usually discussed in terms of optical frequencies
and lasers, e.g. SDI plans to use it to spot and burn missles, but
you can bet your last penny that the Air Force already uses the
scheme I outline above for knocking out enemy radar. And that by
now there are ways the military has of hardening radars to defend against
it.

But the cops don't have that advantage...with sufficient power
their radar transducer would explode. Not very nice. It might hurt
them. As to how much power...well, how much do you think needs to
be absorbed in order to destroy a transducer? The output beam is
close to 100% efficient in terms of target absorption, so that'll
give you your answer. Note that the phase conjugating amplification
step is probably only 10% efficient in use of input energy, though.

Doug Merritt		sun.com!cup.portal.com!doug-merritt