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  2. Radar horizon - Wikipedia

    en.wikipedia.org/wiki/Radar_horizon

    The Clutter Zone is where radar energy is in the lowest several thousand feet of air. This extends to a distance of about 120% of the radar horizon. There are a large number of reflectors on the ground at these elevation angles. Prevailing winds of about 15 mile/hour cause these reflectors to move, and this wind stirs up smaller objects into ...

  3. Radar altimeter - Wikipedia

    en.wikipedia.org/wiki/Radar_altimeter

    The dipole antenna of a radar altimeter of 1947. A radar altimeter (RA), also called a radio altimeter (RALT), electronic altimeter, reflection altimeter, or low-range radio altimeter (LRRA), measures altitude above the terrain presently beneath an aircraft or spacecraft by timing how long it takes a beam of radio waves to travel to ground, reflect, and return to the craft.

  4. Height finder - Wikipedia

    en.wikipedia.org/wiki/Height_finder

    A height finder radar is a type of 2-dimensional radar that measures altitude of a target.. The operator slews the antenna toward a desired bearing, identifies a target echo at a desired range on the range height indicator display, then bisects the target with a cursor that is scaled to indicate the approximate altitude of the target. [7]

  5. Radar signal characteristics - Wikipedia

    en.wikipedia.org/wiki/Radar_signal_characteristics

    At any range, with similar azimuth and elevation angles and as viewed by a radar with an unmodulated pulse, the range resolution is approximately equal in distance to half of the pulse duration times the speed of light (approximately 300 meters per microsecond). Radar echoes, showing a representation of the carrier

  6. 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, propagate 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.

  7. Slant range - Wikipedia

    en.wikipedia.org/wiki/Slant_range

    The slant range (1) is the hypotenuse of the triangle represented by the altitude of the aircraft and the distance between the radar antenna and the aircraft's ground track (point (3) on the earth directly below the aircraft). In the absence of altitude information, for example from a height finder, the aircraft location would be plotted ...

  8. Envelope (radar) - Wikipedia

    en.wikipedia.org/wiki/Envelope_(radar)

    Data is extracted and recorded from the radar system while aircraft, balloons, ships, drones, missiles or other objects are moved within the radar envelope. The recorded data is compared to distance, altitude, and speed of the objects to evaluate the pass-fail criteria. These are the typical shapes of the physical radar envelope. Flattened donut

  9. List of radars - Wikipedia

    en.wikipedia.org/wiki/List_of_radars

    AN/FPS-5 long Range Search Radar; AN/FPS-6 height finder; AN/FPS-7 Long Range Search Radar; AN/FPS-8 Medium Range Search Radar; AN/FPS-10 medium-range search/height finder Radar (stripped-down version of the AN/CPS-6B) AN/FPS-14 Medium-range search Radar; AN/FPS-16 tracking radar; AN/FPS-17 detection radar; AN/FPS-18 Medium-range search Radar