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  2. Over-the-horizon radar - Wikipedia

    en.wikipedia.org/wiki/Over-the-horizon_radar

    The frequency of radio waves used by most radars, in the form of microwaves, travel in straight lines.This generally limits the detection range of radar systems to objects on their horizon (generally referred to as "line of sight" since the aircraft must be at least theoretically visible to a person at the location and elevation of the radar transmitter) due to the curvature of the Earth.

  3. Radar detector - Wikipedia

    en.wikipedia.org/wiki/Radar_detector

    A radar detector is an electronic device used by motorists to detect if their speed is being monitored by police or law enforcement using a radar gun. Most radar detectors are used so the driver can reduce the car's speed before being ticketed for speeding. In general sense, only emitting technologies, like doppler RADAR, or LIDAR can be detected.

  4. Radar - Wikipedia

    en.wikipedia.org/wiki/Radar

    Radar is a system that uses radio waves to determine the distance (ranging), direction (azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method [1] used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain.

  5. Doppler radar - Wikipedia

    en.wikipedia.org/wiki/Doppler_radar

    Doppler effect. The emitted signal toward the car is reflected back with a variation of frequency that depends on the speed away/toward the radar (160 km/h). This is only a component of the real speed (170 km/h). The Doppler effect (or Doppler shift), named after Austrian physicist Christian Doppler who proposed it in 1842, is the difference ...

  6. Radar in World War II - Wikipedia

    en.wikipedia.org/wiki/Radar_in_World_War_II

    Radar in World War II greatly influenced many important aspects of the conflict. [1] This revolutionary new technology of radio-based detection and tracking was used by both the Allies and Axis powers in World War II, which had evolved independently in a number of nations during the mid 1930s. [2] At the outbreak of war in September 1939, both ...

  7. We Tested 6 Radar Detectors to Find the Best - AOL

    www.aol.com/tested-6-radar-detectors-best...

    Valentine V1 Gen 2. A long-time staple in the radar detecting game, we put Valentine's V1 Gen 2 up against the newbies.Right off the bat, the detection distances from this radar detector were the ...

  8. Radar astronomy - Wikipedia

    en.wikipedia.org/wiki/Radar_astronomy

    Radar astronomy. Radar astronomy is a technique of observing nearby astronomical objects by reflecting radio waves or microwaves off target objects and analyzing their reflections. Radar astronomy differs from radio astronomy in that the latter is a passive observation (i.e., receiving only) and the former an active one (transmitting and ...

  9. Radar signal characteristics - Wikipedia

    en.wikipedia.org/wiki/Radar_signal_characteristics

    The pulse width ( ) (or pulse duration) of the transmitted signal is the time, typically in microseconds, each pulse lasts. If the pulse is not a perfect square wave, the time is typically measured between the 50% power levels of the rising and falling edges of the pulse. The pulse width must be long enough to ensure that the radar emits ...