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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. 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.

  5. History of radar - Wikipedia

    en.wikipedia.org/wiki/History_of_radar

    Pulse-Doppler radar (often known as moving target indication or MTI), uses the Doppler-shifted signals from targets to better detect moving targets in the presence of clutter. [78] Monopulse radar (also called simultaneous lobing) was conceived by Robert Page at the NRL in 1943. With this, the system derives error-angle information from a ...

  6. 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.

  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. Synthetic-aperture radar - Wikipedia

    en.wikipedia.org/wiki/Synthetic-aperture_radar

    To create a SAR image, successive pulses of radio waves are transmitted to "illuminate" a target scene, and the echo of each pulse is received and recorded. The pulses are transmitted and the echoes received using a single beam-forming antenna, with wavelengths of a meter down to several millimeters. As the SAR device on board the aircraft or ...

  9. Radar engineering - Wikipedia

    en.wikipedia.org/wiki/Radar_engineering

    Pulse-Doppler radar sensors are therefore more suited for long-range detection, while FMCW radar sensors are more suited for short-range detection. Monopulse : A monopulse feed network, as shown in Fig. 2, increases the angular accuracy to a fraction of the beamwidth by comparing echoes, which originate from a single radiated pulse and which ...