Radar detector

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An early radar detector
An early radar detector

A radar detector, sometimes called a fuzz buster, is an electronic device used by motorists to determine if their speed is being monitored by a radar unit. To do so, police bounce a radio wave off of a moving vehicle with a radar gun or other radar device that determines the vehicle's speed by the Doppler-effect-moderated change in the wave's frequency. Most of today's radar detectors detect signals across a variety of wavelength bands – usually X, K and Ka (as well as Ku, in Europe, also recently approved for use in the U.S).

These devices should not be confused with LIDAR detectors and jammers, or GPS-based warning systems that use a speed camera Point of Interest database to warn a driver who is approaching a speed camera's vicinity.

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Newer speed detection devices use pulsed laser light, commonly referred to as LIDAR, rather than radio waves. Modern radar detectors have been modified to alert to the infrared light emitted by such LIDAR guns. LIDAR detection, however, is not nearly as effective as radar detection because the output beam is very focused. While radar's radio waves can expand to 85 feet across at 1000 feet from their source, LIDAR's light beam expands to only about 6 feet. Also, a police officer targeting a car will most likely aim for the center mass or headlight of the vehicle and, because radar detectors are mounted on the windshield away from the beam's aim, they may not alert at all. Lastly, with such a focused beam, an officer using a LIDAR gun can target a single car in close proximity to others at ranges of up to 3000 feet.

Despite the advent of LIDAR speed detection, radar remains more prevalent because of its lower price relative to LIDAR equipment and the amount of radar equipment already in service. A severe limitation of LIDAR is that it cannot be used while the police car is in motion, because it requires the operator to actively target each target vehicle whereas traditional radar can be operated while the police officer is driving his car.[citation needed] Popularity of LIDAR speed detection is on the rise, though, as costs decline, ease of operability approaches radar, and existing radar equipment reaches its end-of-service life and is rotated out of service.

Popular radar detector brands include Beltronics, Cobra, Escort, Valentine One, and Whistler.

[edit] Radar Scrambling

Although some companies advertise that their radar detectors can 'scramble' or 'absorb' radar and LIDAR (such as Rocky Mountain Radar), many or all of their products do not affect radar and laser equipment due to the low power intake from the device versus the high power that bounces off a vehicle.[1]

In the USA, it is illegal to sell or possess any such products that transmit radar signals intended to jam radar equipment.[2] Actively transmitting on an FCC licensed frequency without a license is a violation of FCC regulations and a felony. LIDAR jammers are legal in most states and are regulated, much like police LIDAR guns, by the FCC as Class I laser devices.

[edit] Legality

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In some countries and areas, such as those listed below, using or possessing a radar detector is illegal and may result in fines, seizure of the device, or both. These prohibitions generally are introduced under the premise that a driver who uses a radar detector will pose a greater risk of accident than a driver who does not. However, some research has found that the opposite is true. The 2001 Mori report suggests that radar detector users posed a 28% less risk of accident.

 (§ 375)  30. It shall be unlawful for any person to  operate  a  motor  vehicle
 with  any  object placed or hung in or upon the vehicle, except required
 or permitted equipment of the vehicle, in such a manner as  to  obstruct
 or interfere with the view of the operator through the windshield, or to
 prevent  him from having a clear and full view of the road and condition
 of traffic behind such vehicle.

[edit] RDDs - Radar Detector Detectors

Main article: Radar detector detector

RADAR detectors are built around a superheterodyne receiver, which has a local oscillator that radiates slightly, so it is possible to build a radar-detector detector, which detects such emissions (usually the frequency of the radar type being detected, plus about 10 MHz). The VG-2 Interceptor was the first device developed for this purpose, but has since been eclipsed by the Spectre III. [9] This form of "electronic warfare" cuts both ways - since detector-detectors use a similar superheterodyne receiver, many early "stealth" radar detectors were equipped with a radar-detector-detector-detector circuit, which shuts down the main radar receiver when the detector-detector's signal is sensed, thus preventing detection by such equipment. This technique borrows from ELINT surveillance countermeasures. In the early 1990s, BEL-Tronics, Inc. of Ontario, Canada (where radar detector use is prohibited) found that the local oscillator frequency of the detector could be altered to be out of the range of the VG-2 Interceptor. This resulted in detector manufacturers responding by changing their local oscillator frequency. Today, practically every radar detector on the market is immune to the VG-2 Interceptor[citation needed].

[edit] See also

[edit] References

  1. ^ Passive Radar Jammers
  2. ^ FCC Ban
  3. ^ Road Traffic (Miscellaneous) Variation Regulations 2003. SA State Government (2003).
  4. ^ Traffic Infringement Notice. Department of Infrastructure, Energy and Resources.
  5. ^ Travel Canada's Northwest Territories
  6. ^ United States Department of State: Consular Information Sheet for Canada
  7. ^ U.S. RADAR Detector Laws
  8. ^ NY State Law Database: http://public.leginfo.state.ny.us/menugetf.cgi?COMMONQUERY=LAWS
  9. ^ Radar Detector Detector (RDD)