[amsat-bb] Re: Government control has exceeded constitutional limitations.
Nate Duehr
nate at natetech.com
Tue Apr 24 13:06:33 PDT 2007
On 4/24/07, John Magliacane <kd2bd at yahoo.com> wrote:
> The discussion points out that this RADAR system has been around for quite a
> number of years and is an extremely agile system, so it should be immune to
> simple forms of interference caused by regular Amateur Radio communications.
>
> If PAVE PAWS is *THAT* easily interfered with, and that fact is not a secret,
> what does that say about its usefulness?
It is pretty simple to infer that the real thing being interfered with
probably isn't PAVE PAWS, of course.
The rest is just speculation. There were upgrades in 2001, but they
don't seem to be related to today's issue.
http://www.fas.org/spp/starwars/program/uewr.htm
Additionally, the exact takeoff angles of the phased arrays and the
direction of those arrays is known... as it was part of the
environmental impact statements made for RF exposure for all the
active sites in the early 2000's.
http://www.fas.org/spp/starwars/program/eisnmddraft/uewr.pdf
What we know from the above:
- The antenna is capable of a 2.2 degree beamwidth (3dB)
- The two faces of the station only cover 240 degrees of the sky
around the facility.
- The beam center is never is pointed lower than 3 degrees above the
horizon and is launched from 52' above ground level.
(Putting the main beam of this very tight antenna system 131' into the
air by the time it's 2200' from the antenna...at its LOWEST to the
horizon useage, according to the above document, their math, not
mine.)
Hard to believe ham repeaters are bothering something that
well-engineered. Sounds like they seriously cocked-up an upgrade on
the receive side, or they're trying some side-scatter receiving
techniques from other locations and the ham repeaters are screwing up
their results. Just a guess.
If you had a 340W UHF system capable of transmitting in a 2.2 degree
beamwidth and hitting things and bouncing off them, wouldn't you try
seeing the bounces from other places, too? (GRIN).
Sounds like they need some smarter RF engineers, if they can't figure
out how to filter out the effects of constant-carrier FM sources like
ham repeaters.
Nate WY0X
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