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  2. Radar signal characteristics - Wikipedia

    en.wikipedia.org/wiki/Radar_signal_characteristics

    Ground targets further than this range cannot be detected, so the PRF can be quite high; a radar with a PRF of 7.5 kHz will return ambiguous echoes from targets at about 20 km, or over the horizon. If however, the PRF was doubled to 15 kHz, then the ambiguous range is reduced to 10 km and targets beyond this range would only appear on the ...

  3. Radar - Wikipedia

    en.wikipedia.org/wiki/Radar

    Coastal radar systems, over-the-horizon (OTH) radars; 'high frequency' VHF: 30–300 MHz: 1–10 m: Very long range, ground penetrating; 'very high frequency'. Early radar systems generally operated in VHF as suitable electronics had already been developed for broadcast radio.

  4. High frequency - Wikipedia

    en.wikipedia.org/wiki/High_frequency

    High frequency (HF) is the ITU designation [1] [2] for the band of radio waves with frequency between 3 and 30 megahertz (MHz). ... Over-the-horizon radar systems;

  5. 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.

  6. List of radar types - Wikipedia

    en.wikipedia.org/wiki/List_of_radar_types

    The frequency selection of weather radar is a performance compromise between precipitation reflectivity and attenuation due to atmospheric water vapor. Some weather radars uses doppler shift to measure wind speeds and dual-polarization for identification of types of precipitations.

  7. 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 ...

  8. High-tech radar used in Ukraine-Russia war to be ... - AOL

    www.aol.com/high-tech-radar-used-ukraine...

    “Basically what a radar does is a radar bounces radio waves off of objects," said Brost, adding that the Robin radar can also read a drone's radio frequency: "There’s a sophisticated term ...

  9. Doppler radar - Wikipedia

    en.wikipedia.org/wiki/Doppler_radar

    Radar systems operating at extremely high frequency offer enhanced Doppler resolution for a given coherent processing interval. [18] This increased resolution allows access to micro-Doppler signatures (MDSs), where micro-Doppler refers to Doppler modulations caused by the oscillatory movement of a target's structural components, in contrast to ...