On 4/24/07, John Magliacane kd2bd@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