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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. 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.

  5. 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;

  6. Radio spectrum - Wikipedia

    en.wikipedia.org/wiki/Radio_spectrum

    Radar-frequency bands according to IEEE standard [17] Band designation Frequency range Explanation of meaning of letters; HF: 0.003 to 0.03 GHz: High frequency [18] VHF: 0.03 to 0.3 GHz: Very high frequency [18] UHF: 0.3 to 1 GHz: Ultra-high frequency [18] L: 1 to 2 GHz: Long wave S: 2 to 4 GHz: Short wave C: 4 to 8 GHz: Compromise between S ...

  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. Ground-penetrating radar - Wikipedia

    en.wikipedia.org/wiki/Ground-penetrating_radar

    GPR uses high-frequency (usually polarized) radio waves, usually in the range 10 MHz to 2.6 GHz. A GPR transmitter and antenna emits electromagnetic energy into the ground. When the energy encounters a buried object or a boundary between materials having different permittivities, it may be reflected or refracted or scattered back to the surface ...

  9. 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 ...