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  2. Radar signal characteristics - Wikipedia

    en.wikipedia.org/wiki/Radar_signal_characteristics

    The change of repetition frequency allows the radar, on a pulse-to-pulse basis, to differentiate between returns from its own transmissions and returns from other radar systems with the same PRF and a similar radio frequency. Consider a radar with a constant interval between pulses; target reflections appear at a relatively constant range ...

  3. Radar - Wikipedia

    en.wikipedia.org/wiki/Radar

    Radar is a system that uses radio waves to determine the distance (), 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.

  4. Weather radar - Wikipedia

    en.wikipedia.org/wiki/Weather_radar

    Weather radar in Norman, Oklahoma with rainshaft Weather (WF44) radar dish University of Oklahoma OU-PRIME C-band, polarimetric, weather radar during construction. Weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, and estimate its type (rain, snow, hail etc.).

  5. Pulse-repetition frequency - Wikipedia

    en.wikipedia.org/wiki/Pulse-repetition_frequency

    The pulse-repetition frequency (PRF) is the number of pulses of a repeating signal in a specific time unit. The term is used within a number of technical disciplines, notably radar. In radar, a radio signal of a particular carrier frequency is turned on and off; the term "frequency" refers to the carrier, while the PRF refers to the number of ...

  6. Doppler radar - Wikipedia

    en.wikipedia.org/wiki/Doppler_radar

    Early Doppler radars included CW, but these quickly led to the development of frequency modulated continuous wave radar, which sweeps the transmitter frequency to encode and determine range. With the advent of digital techniques, Pulse-Doppler radars (PD) became light enough for aircraft use, and Doppler processors for coherent pulse radars ...

  7. Continuous-wave radar - Wikipedia

    en.wikipedia.org/wiki/Continuous-wave_radar

    Continuous-wave radar (CW radar) is a type of radar system where a known stable frequency continuous wave radio energy is transmitted and then received from any reflecting objects. [1] Individual objects can be detected using the Doppler effect , which causes the received signal to have a different frequency from the transmitted signal ...

  8. Radiodetermination - Wikipedia

    en.wikipedia.org/wiki/Radiodetermination

    A radiodetermination station uses reception of radio waves in order to determine the location of an object, under the condition that this thing is reflecting and/or transmitting radio waves. This designation may also be the collective name of any radar set in general, up to target location, illuminating, acquisition and tracking, as well as ...

  9. 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.