Path: utzoo!attcan!uunet!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!cbnews!cbnews!military
From: yarvin-norman@CS.YALE.EDU (Norman Yarvin)
Newsgroups: sci.military
Subject: Airborne Radar
Message-ID: <1991Feb28.052606.10693@cbnews.att.com>
Date: 28 Feb 91 05:26:06 GMT
Sender: military@cbnews.att.com (william.b.thacker)
Organization: AT&T Bell Laboratories
Lines: 30
Approved: military@att.att.com



From: yarvin-norman@CS.YALE.EDU (Norman Yarvin)

I have a few questions about radar.  First, in a radar searching for
airplanes, to get a three-dimensional picture the beam must be scanned over
all combinations of two angles.  This seems like it would take unduly long,
to give any precision.  A lower bound on resolution is given by the
wavelength, but how precise are radars in practice?  Do many of them simply
not determine height?  Do they determine height in some other manner than
scanning the beam TV-style?

Second, radars on fighters seem to be located in the nose cone, and to point
forward.  The AWACS planes seem to have a large radar, in the shape of a
disc attached to the top of the plane.  What is the mechanism these radars
use to scan their beams?  I know of two classes of mechanisms: phased-array
grids, and the rotation of an antenna.  These don't need to be visible; they
might be concealed/protected behind radar-transparent material.  Is the
AWACS's disk shielding a rotating antenna?  And what sort of mechanism can
fit in a fighter's nose?

Second, the limit on a radar's range is due to a combination of antenna
geometry and output power.  Is it the AWACS's superior antenna or its higher
power that gives it range advantages over fighter radars?


Norman Yarvin					yarvin-norman@cs.yale.edu
"...those skilled at attack maneuver in the highest heights of the sky.  Thus
they can preserve themselves and gain complete victory."
	-- Sun Tzu, _The Art of War_