Need a minimum safe distance for a Millimeter Wave Radar

[Wolfala]

This is what we are testing:

http://www.amphitech.com/pdf/PSRwpFeb2007.pdf


I believe it operates in the 77 GHz range.

[Suave]

I think it has a ranger of 2.5 miles.

Take a radars pulse rate and divide it by the speed of light, that will give you it's radius.

[Odee]

Working on a boombox car destroyer are you?   Ramp the amp, and a EMP burst later, now more bass thumping headaches..

Now if only the range of that could be a couple hundred feet and in a tight beam...  Several local punks would be respecting the family ear drums as they smell melting sheathes and popping circuits.

[Wolfala]

the industrial limit for microwave power exposure since the 50’s has been 10mW/cm^2, and for a consumer microwave oven, the acceptable leakage is 5mW/cm^2 at 5cm.  The power per unit are should go as TotalPower/(Area of Spherical Surface at a given distance).  Our PSR device is only 50Watts, omnidirectional, so at a distance of 100cm the power per unit area is something like



50W / (4 Pi * (100cm)^2) = 0.4 mW/cm^2



So unless any of us have a pacemaker, we're probably pretty safe as long as you don’t hang out super close to it. At the 77GHz frequency, the “skin-depth” (penetration distance) is about 1 micron in metal.  Put another way, if you wrapped yourself up in a sheet of tinfoil you’d be shielded from all the radiation.  And you’d look pretty cool, too.

So, figuring a minimum safe distance for this device is 1.5 meters.

[Chairboy]

For a boombox destroying EMP, I don't know what all them scientists do, but back on the farm, we'd just wind ourselves a coil out of copper wire around a piece of stump remover or some homemade C4 (the faster the detonation, the sharper the pulse), then gradually charge it up until it had a really high potential voltage.  It'd take about a half hour, you've got to be careful to avoid melting the copper wiring.  

Then, we'd blow the stick (at the end where the charge leads are), so the circuit is isolated in the first millisecond and, as it detonates, it would force the wave front forward through the coil until it ran out of room and expended itself in a high powered electromagnetic pulse.  We'd stick the whole thing inside an old faraday isolated 55 gallon drum with one end cut off to direct the EMP in a single direction, and that sucker'd knock out car ignitions from a quarter mile away.

Of course, this was just good old country fun, I'm sure the science folks do things fancier.

Gitmo for me in 3...2...1...

[Suave]

Ah, I thought you meant safe from detection. When you said testing I of course presumed you were planning on stealing a boat or something.