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  2. Radar signal characteristics - Wikipedia

    en.wikipedia.org/wiki/Radar_signal_characteristics

    The pulse width must be long enough to ensure that the radar emits sufficient energy so that the reflected pulse is detectable by its receiver. The amount of energy that can be delivered to a distant target is the product of two things; the peak output power of the transmitter, and the duration of the transmission.

  3. Pulse-Doppler radar - Wikipedia

    en.wikipedia.org/wiki/Pulse-Doppler_radar

    Aircraft and some missiles exploit this weakness using a technique called flying below the radar to avoid detection (nap-of-the-earth). This flying technique is ineffective against pulse-Doppler radar. Pulse-Doppler provides an advantage when attempting to detect missiles and low observability aircraft flying near terrain, sea surface, and weather.

  4. Pulse-repetition frequency - Wikipedia

    en.wikipedia.org/wiki/Pulse-repetition_frequency

    Medium PRF is used with Pulse-Doppler radar, which is required for look-down/shoot-down capability in military systems. Doppler radar return is generally not ambiguous until velocity exceeds the speed of sound. A technique called ambiguity resolution is required to identify true range and speed. Doppler signals fall between 1.5 kHz, and 15 kHz ...

  5. Low-frequency radar - Wikipedia

    en.wikipedia.org/wiki/Low-frequency_radar

    If the radar wavelength is roughly twice the size of the target, a half-wave resonance effect can still generate a significant return. However, low-frequency radar is limited by shortage of unused frequencies, lack of accuracy given the long wavelength, and by the radar's size, making it difficult to transport and making for an easy target.

  6. 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.

  7. Pulsed radiofrequency - Wikipedia

    en.wikipedia.org/wiki/Pulsed_radiofrequency

    The duty cycle for a pulsed radio frequency is the percent time the RF packet is on, 4.2% for this example ([0.042 ms × 1000 pulses divided by 1000 ms/s] × 100). The pulse packet form can be a square, triangle, sawtooth or sine wave. [1] In several applications of pulse radio frequency, such as radar, [2] times between pulses can be modulated.

  8. Pulse-Doppler signal processing - Wikipedia

    en.wikipedia.org/wiki/Pulse-Doppler_signal...

    Pulse-Doppler begins with coherent pulses transmitted through an antenna or transducer. There is no modulation on the transmit pulse. Each pulse is a perfectly clean slice of a perfect coherent tone. The coherent tone is produced by the local oscillator. There can be dozens of transmit pulses between the antenna and the reflector.

  9. List of radar types - Wikipedia

    en.wikipedia.org/wiki/List_of_radar_types

    The radar measures the distance to the reflector by measuring the time of the round trip from emission of a pulse to reception, dividing this by two, and then multiplying by the speed of light. To be accepted, the received pulse has to lie within a period of time called the range gate .