BHB3@PSUVM.BITNET (11/22/89)
I finally got the long awaited information I requested on the laser speed
measuring device(laser radar) that is/will be being tested soon by many police
agencies throughout the country. The following is the entire un-edited text
of the information bulletin send out by Internation Measurement to police
departments.
LASER SPEED GUN
International Measurement and Control Company has developed five laser-based
measuring and positioning systems over the last three years. Most recently
the company developed a laser that is being used by the U.S. Navy in a
sophisticated missle test system. THE IMC laser is mounted in one aircraft
and used to track another aircraft. The laser provides a continuous update as
to the distance detween the two aircraft. Through the design of this and other
laser systems IMC has developed the capability to produce a laser that can be
used to measure car velocity. The laser you are seeing today is almost
identical to the laser used by the Navy. We have modified it to measure
velocity, but it is by no means a final product. The final product will be
smaller, lighter, and quciker. Extensive work is being dome that will provide
safeguards to guarantee accurate readings.
It is our understanding that the law enforcement community has been seeking a
method for positive identification of vehicles as they are being clocked. The
laser instrument provides this capability as you will witness today. The
instrument must be aimed through a scope similar to a rifle, therefore the
officer using the instrument knows exactly which car is being targeted. Laser
cannot be detected by radar detectors and is not vulnerable to radio interfer-
ence. In addition it would be very difficult to develop a laser detector
because of the laser's inherent narrow beam. The instrument will distinguish
between an approachin and departing target which would enable clocking of
a car moving the same direction while in transit.
Below please find the projected specifications of the IMC laser which will
be released within the next 6 - 9 months:
SPECIFICATIONS
(1) RANGE 1000-2000 feet
(2) TARGET SPEED +/- 200 mph
ACCURACY +/- 1 mph
AQUISITION TIME 0.5 seconds
BEAM WIDTH 4 ft. at 1000 ft. range
WEIGHT 5 lbs.
SIZE 4" X 6" X 7"
EYE SAFETY FDA Class 1/CFR 21
(1) The range will vary depending upon the reflective qualities of the target
surface.
(2) The system will give a positive speed reading for an approaching target
and a negative reading for a departing target. It will also give an accurate
zero reading.
International Measurement . 200 E. Mineral #5 . Littleton, Colorado 80122
(303) 797-7722
End of Text
This demo bulleting is about 3 months old so the 6 - 9 month time frame is
about 3 - 6 months now. The rumor mill is that the Michigan State Police and
a
the Kansas State Police have test units already. The unit initially will
probably only be used from a stationary police vehicle, since a way of
determining the police vehicles speed would be necessary. They would have to
use their radar unit for that, which would defeat the purpose of the device
anyway. The company rep I talked to said the device would cost $3000. The
moral of the post is don't throw away your radar detectors for a long time,
just don't try to think they will be foolproof.
Brent H. Beslertomcat@cbnewsl.ATT.COM (fred.j.shubert) (11/23/89)
In article <89325.164006BHB3@PSUVM.BITNET>, BHB3@PSUVM.BITNET writes: > > LASER SPEED GUN > > SPECIFICATIONS > > (1) RANGE 1000-2000 feet > (2) TARGET SPEED +/- 200 mph > ACCURACY +/- 1 mph > AQUISITION TIME 0.5 seconds > BEAM WIDTH 4 ft. at 1000 ft. range > WEIGHT 5 lbs. > SIZE 4" X 6" X 7" > EYE SAFETY FDA Class 1/CFR 21 > > (1) The range will vary depending upon the reflective qualities of the target > surface. > (2) The system will give a positive speed reading for an approaching target > and a negative reading for a departing target. It will also give an accurate > zero reading. > > International Measurement . 200 E. Mineral #5 . Littleton, Colorado 80122 > (303) 797-7722 Are they willing (or have they indicated) the power output of the laser? (Seems a bit weak; beam width). Can we find out what type of laser and wavelength? Seems possible to build a "jammer" for this by flooding the area in front of and behind of your car as you book to work/play. (Assuming it can be done safely) Fred J. Shubert | "You haven't lived until you've seen a 'cat fly!!!" AT&T Bell Labs |----------------------------------------------------- Whippany, N.J. | DISCLAIMER: All views are that of my own. PERIOD. Ma-Bell 201-386-3094 | Who else could be so 'cat crazy!! | _ | | /^ ^\ | F-14D ____________|_( . )_|____________ SUPERTOMCATS --*/--|_| (___) |_|--\*-- RULE * O O * (I Love 'Em) Let's turn and burn!!
dave@umbc5.umbc.edu (David A Freeman) (11/23/89)
In article <89325.164006BHB3@PSUVM.BITNET> BHB3@PSUVM.BITNET writes: >I finally got the long awaited information I requested on the laser speed > > LASER SPEED GUN Now this is a prime candidate for a jammer. I assume all that is needed is an IR laser diode with a lens to disperse the beam about 25 degrees. A power supply would generate pulses at a frequence that would screw up the guns timing ability. This could be coupled with an IR photo transistor that reacts to IR pulses of the proper wavelength. Any idea what wavelength the beam is? How about the guns pulse frequence and interval? dave David Freeman Systems Programmer dave@umbc3.umbc.edu Univ Md Baltimore County dave@umbc !bitnet
jwabik@uc.msc.umn.edu (Jeff Wabik) (11/23/89)
In article <89325.164006BHB3@PSUVM.BITNET>, BHB3@PSUVM.BITNET writes: > I finally got the long awaited information I requested on the laser speed > measuring device(laser radar) that is/will be being tested soon by many police > agencies throughout the country. The following is the entire un-edited text > of the information bulletin send out by Internation Measurement to police > departments. > [ ... ] The question is: How easy/difficult will this be to jam? I know virtually nothing about this technology (other than the obvious), but, wouldn't creating "light noise" (i.e. Have your own wide-beam laser strapped to the front of your car sending all sorts of bizarre patterns and such), much the same as RF noise for Radar applications, effectively jam the "laser radar"? Seems easy, and also seems as though the FCC couldn't control it. Then again, I spoze if this were possible the Navy wouldn't be using it? -Jeff
welty@lewis.crd.ge.com (richard welty) (11/23/89)
[i'm not sure i understand what this is doing crossposted to misc.consumers, as there are no consumer issues i know of associated with the topic. therefore, i'm deleting it from the followup-to line -- rpw] In article <807@uc.msc.umn.edu>, Jeff Wabik writes: *In article <89325.164006BHB3@PSUVM.BITNET>, BHB3@PSUVM.BITNET writes: *>... about infrared speed measuring devices ... *The question is: How easy/difficult will this be to jam? how legal will it be to jam? this may fall pretty easily under `obstructing justice' and `interfering with police officer' type laws. * (i.e. Have your own wide-beam laser what's a wide-beam laser? richard -- richard welty 518-387-6346, GE R&D, K1-5C39, Niskayuna, New York ..!crdgw1!lewis.crd.ge.com!welty welty@lewis.crd.ge.com ``i've got a girlfriend with bows in her hair, and nothing is better than that'' -- David Byrne
koziarz@halibut.nosc.mil (Walter A. Koziarz) (11/23/89)
Get set to buy those 'Edmunds Scientific' LASERs! The transmission of light is not regulated by the FCC so we can JAM the LASER toys!!
BHB3@PSUVM.BITNET (11/28/89)
I am working on getting the frequency and output power of the device. Putting
out anything but the same frequency it uses will do no good. Also frankly a
police scanner is the most effective countermeasure. They won't be able to use
the laser device while moving for a while yet.
Brent H. BeslerBHB3@PSUVM.BITNET (11/28/89)
The critical facts needed are the output power and the frequency of the
device. The reflectance off of a car surface is going to be pretty week, so
the thing has to have a quite sensitive detector for that frequency. It is
probably possible to overwhelm the detector with light of the same frequency.
IR light is of couse invisible to the human eye, so even if you had a bright
IR strobe, it would be too obvious. It is going to be extremely obvious
to the cop that you are jamming it with high intensity light, since the
device is scope aimed(i.e. He knows who you are right away). An effective
jammer is going to have to cause it to register the correct speed. Since the
device works on succesive distance measurements, you would have to know the
pulse rate it puts out. I would say a police scanner would be the best real
countermeasure.
Brent H. BeslerBHB3@PSUVM.BITNET (11/28/89)
I have two good guesses on the wavelength of the laser device: 0.9 microns being the most common cheap GaAs laser diodes or 1.54 micron being in the "eye-safe" zone for which diode laser also exist. I am checking the eyesafety standards ANSI publication Z 136.1 - 1980 to see if that will give me a clue to the frequency and/or output power
batman@watsci.uwaterloo.ca (Marcell Stoer) (11/29/89)
The laser beam will probably be modulated ( ie chopped). This will make jamming difficult, since you don't know the chopping frequency. This in turn increases the sensitivity of the measurement (phase sensitive detection) . 0.9 microns is near IR and can be seen by the human eye if the beam is scattered by a medium (ie glass does it all the time). You'd be able to see the beam with an IR viewer ( they cost about $2K pre-built) if you're interested in watching those kind of things. Currently, radar is not a perfect speed detection technique either, and can be fooled by a moving cop car or when multiple cars are being scanned. The question is, is there less noise at 0.91 microns +/- a bit than at radar wavelengths. And is that sufficient to make this technique a superior one ? Marcell Stoer Centre for Molecular Beams And Laser Chemistry .
jeffg@shamu.WV.TEK.COM (Jeff C. Glover) (11/30/89)
In article <89331.143759BHB3@PSUVM.BITNET> in misc.consumers, Brent H. Besler writes: > [discussion of infrared speed-measuring device ommitted] > I would say a police scanner would be the best real > countermeasure. Most of the time the speed measuring is done by a single officer. This means the only communications will be a license plate check that you'll have no idea of where it's coming from unless the officer deems it important to the dispatcher. Even if they're running a speed trap with multiple cars, the communications is often of the form 'Red Camaro, Idaho Plates, 75', again with no indication of location. Here in the Portland area they use the same frequency that they use for dispatch, which means that the transmission could have come from anywhere within about 500 square miles. Besides, it's illegal in some states to carry a mobile police-band receiver. Not that such a law stops anyone. We were talking about evading the police anyway, right? :-) Jeff Disclaimer: All opinions expressed within this article are mine.
besler@egrunix.UUCP (Brent Besler) (11/30/89)
The atmoshpere is pretty transparent at 0.91 microns. The laser speed measuring device is "better" than radar I think, because the beam is much more narrow 0.22 degrees vs. 15 or so for K band radar. It is rifle sight aimed, so the cop will know which car he is clocking.