🚀 go-pugleaf

In article <3331@kitty.UUCP> larry@kitty.UUCP (Larry Lippman) writes:
+In article <661.24E1D0E5@bigtime.fidonet.org>, hugo@bigtime.fidonet.org (Hugo) writes:
+>   Of such interest is the newest addition to the home ECM scene, the
+> aircraft detector......
+
+	Short of placing an Adcock antenna array or an equivalent device on
+the roof of a vehicle, there is no way to ascertain "course" of an aircraft
+based upon a radio emission.  For the application at hand, there is no
+way whatsoever to ascertain "distance" of an aircraft.
+
Although I agree with you in the practical sense, there IS a way to 
ascertain distance from AIRCRAFT which are equiped with an ATC
transponder, a device based upon a radio emmission.  Through the 
process of pulsed interrogation and reply, distance, and course can
be computed, and, with altitude encoding, altitude can also be determined.

Now the problem becomes identifying which aircraft belongs to the
law enforcement agency, and which one is a private aircraft sightseeing
over the freeway.

With a simpler method, you can determine that an aircraft is nearby 
(approx 1-2 miles) by monitoring the response transmission with a 
scanner such as the RS2004/5.  You cannot tell if they are in front, 
beside, or behind you, and you can't tell if they are 500 or 5000 feet 
above you, and you can't tell if they are checking your speed, or just
following the freeway.

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