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  2. History of radar - Wikipedia

    en.wikipedia.org/wiki/History_of_radar

    The history of radar (where radar stands for radio detection and ranging) started with experiments by Heinrich Hertz in the late 19th century that showed that radio waves were reflected by metallic objects. This possibility was suggested in James Clerk Maxwell 's seminal work on electromagnetism.

  3. Radar - Wikipedia

    en.wikipedia.org/wiki/Radar

    The radar mile is the time it takes for a radar pulse to travel one nautical mile, reflect off a target, and return to the radar antenna. Since a nautical mile is defined as 1,852 m, then dividing this distance by the speed of light (299,792,458 m/s), and then multiplying the result by 2 yields a result of 12.36 μs in duration.

  4. 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 ...

  5. Project Diana - Wikipedia

    en.wikipedia.org/wiki/Project_Diana

    The first successful echo detection came on 10 January 1946 at 11:58am local time by Harold Webb and Herbert Kauffman. [5] Project Diana marked the birth of radar astronomy later used to map Venus and other nearby planets, and was a necessary precursor to the US space program.

  6. Aleksandr Popov (physicist) - Wikipedia

    en.wikipedia.org/wiki/Aleksandr_Popov_(physicist)

    Aleksandr Popov (physicist) Alexander Stepanovich Popov (sometimes spelled Popoff; Russian: Александр Степанович Попов; March 16 [O.S. March 4] 1859 – January 13 [O.S. December 31, 1905] 1906) was a Russian physicist who was one of the first people to invent a radio receiving device. [1][2][3] Popov's work as a teacher ...

  7. Space-based radar - Wikipedia

    en.wikipedia.org/wiki/Space-based_radar

    Space-based radar (SBR) is a proposed constellation of active radar satellites for the United States Department of Defense. The SBR system would allow detection and tracking of aircraft, ocean-going vessels (similar to the Soviet US-A program), and potentially land vehicles from space. This information would then be relayed to regional and ...

  8. 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.

  9. Christian Hülsmeyer - Wikipedia

    en.wikipedia.org/wiki/Christian_Hülsmeyer

    Christian Hülsmeyer. Christian Hülsmeyer (Huelsmeyer) (25 December 1881 – 31 January 1957) was a German inventor, physicist and entrepreneur. He is credited with the invention of radar, although his apparatus, called the "Telemobiloscope," could not directly measure distance to a target. The Telemobiloscope was, however, the first patented ...