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From: scw@CS.UCLA.EDU
Newsgroups: sci.electronics
Subject: Re: radar countermeasures
Message-ID: <9879@shemp.CS.UCLA.EDU>
Date: 1 Mar 88 15:45:25 GMT
References: <4596@pucc.Princeton.EDU> <20271@bu-cs.BU.EDU>
Sender: news@CS.UCLA.EDU
Reply-To: scw@CS.UCLA.EDU (Stephen C. Woods)
Organization: UCLA Computer Science Department
Lines: 15

What you really need is not a Xponder (mode C?) but a Jammer,
Police Radar is really a CW Doppler radar, what you need to do is
detect an incoming signal (on the band in question) and transmit a
signal that varies its frequency so that the recieved signal appears to
be from a target whose speed is varying from -200 to +200 MPH over a period
of about 1 second, then listen for ~.1 sec to see if he's still transmitting.
This will keep the police radar from locking onto your (weaker) reflected
signal. His gun will needs a fairly stable signal to lock onto. The nice
thing about this is that unless you regulary drive in the 100+ MPH range
his radar will never get any reasonable speed for your car (from either
direction).
<scw>

Stephen C. Woods; UCLA SEASNET; 2567 BH;LA CA 90024; (213)-825-8614
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