NetNews Usenet Archive 1993 #3/NN_1993_3.iso/spool/sci/electron/23184

Text File | 1993-01-21 | 5.2 KB | 125 lines

Newsgroups: sci.electronics
Path: sparky!uunet!zaphod.mps.ohio-state.edu!sdd.hp.com!ux1.cso.uiuc.edu!news.iastate.edu!vincent1.iastate.edu!sehari
From: [e-mail] (Babak Sehari)
Subject: Re: RADAR, RADAR ECM, and RADAR ECCM
Message-ID: <[e-mail]>
Originator: [e-mail]
Sender: [e-mail] (USENET News System)
Organization: Iowa State University of Science and Technology, Ames, Iowa.
References: <[e-mail]> <[e-mail]>
Date: Fri, 22 Jan 1993 02:44:06 GMT
Lines: 112

In <[e-mail]> [e-mail] (Shaen Bernhardt) writes:


>originally I sent this as a letter, but it occurs to me that I might be
>mistaken on some points, or might have some points that others might
>like to hear so....:

>>To: [e-mail]
>>Subject: Re: RADAR, RADAR ECM, and RADAR ECCM
>>Newsgroups: sci.electronics,rec.autos.driving
>>In-Reply-To: <[e-mail]>
>>Organization: Boston University, Boston, MA, USA
>>Cc:
>>Bcc:
>
>In article <[e-mail]> you write:
>>
>>
>>     I am currently an electrical engineering student with a vast
>>interest in Microwave Engineering and RADAR Systems Engineering.
>
>[Stuff Deleted]
>
>It's nice to see someone else interested in this material.
>I have studied the functionality and process of speed measurement by
>radar for some time (Being an avid speeder)
>I bought my first radar gun (never had or tried to get a license) when I
>was 14.
>
>
>>     However, with all that I have learned and all the books I have
>>looked through, I cannot find an answer to this question:
>
>>     In NJ, the only police RADAR unit that is legally used by State
>>Police is the MPH Industries K-55 X-band RADAR unit. (There are three
>
>[Stuff Deleted]
>I have had some experience with these units.
>
>>     These units also have a jack for an option for an Electronic
>>Counter Measure detection/ECCM unit to be attached. I already owned a
>
>[Stuff deleted]
>
>>I was able to obtain one of these optional ECCM units. However, all
>>the unit is is a third antenna, that's battery operated, and it
>>displays a third vehicle/object speed. I tried using the unit against
>>an X-band spot jammer, and the unit was also fooled by the jammer
>>signal. So what is the purpose of this ECCM unit, what is it supposed
>>to do, and how is it supposed to do it? What is the purpose of having
>>the unit being battery operated? I was not able to get a manual with
>>the ECCM unit, so I can't tell you anything more than I observed.
>
>I have never played with the ECCM units, but I have talked with troopers
>and designers who have.  My impression is that they serve one purpose only,
>and that is to identify other sources of emissions... to identify a vehicle
>transmitting, and thus facilitate capture.. NOT to defeat a jammer, only
>to verify its presence.
>
>I would assume that the speed reading is a passive reader designed to
>pickup the signal of a jammer and display the speed it is transmitting.
>
>Theoretically the use of said unit would be as such:
>
>1>  Trooper with instant on/constant speed measureing unit observes a
>car traveling at what he/she feels to be a unusually high speed.
>(Note that trooper has the ECCM unit)
>
>2>  Trooper iluminates the target vehicle, but gets only a 57 mph reading
>(Despite the fact that the offending vehicle seems to be traveling at 90+)
>
>3>  Trooper deactivates the radar transmitter (freezing the reading 57mph)
>
>4>  The ECCM unit (not powered by the trigger on the k-55 unit) continues
>to recieve and display 57 in the absence of any trooper transmission
>
>5>  As Trooper is not transmitting, yet a signal is still present:  Another
>transmission must be present, and transmitting at 57mph.
>

The ECM unit will shut itself off and on as soon as it detect  transmission.
This switching can take place at very high speed.  Other wise, the car
is a red becon, and could be chased by FCC officials.  So, your ECCM does not
work with this ECM.

>This is consistant with the typical jammer methods I have observed.
>1>  Jammers are of two types:  Active or Passive/Active.
>
>The active types just transmit 57 mph (Or whatever they are set to) all the
>time.  (Setting off all the radar detectors within range I might add)
>
>The Passive Actives wait until they recieve a signal (via external speaker
>jack in an escort/pasport detector for example) and THEN transmitt 57mph
>
>Either way....
>
>1>  With the ACTIVE jammer, the trooper will receive a signal without
>transmitting.  (Assumeably this will result in a display on the ECCM unit)
>
>2>  With the Passive/Active jammer, the trooper will receive a signal
>without transmitting (Having triggered the transmitter)  I believe
>all the transmitters have a good deal of lag after the trooper lets
>up on the trigger.  (Jamming transmitters that is)
>

As mentioned in above, the ECM Unit shot itself off and on.  Also, another
type of ECM could be contructed that any time it receives Radar signal it
send high energy plus to burn the input circuit of the police radar.

                         With highest regards,
                              Babak   Sehari.
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