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Radar is a system that uses radio waves to determine the distance (ranging), 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.
Doppler effect. The emitted signal toward the car is reflected back with a variation of frequency that depends on the speed away/toward the radar (160 km/h). This is only a component of the real speed (170 km/h). The Doppler effect (or Doppler shift), named after Austrian physicist Christian Doppler who proposed it in 1842, is the difference ...
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.).
Over-the-horizon radar. How a skywave OTH radar works: A powerful shortwave signal from a large transmitting antenna (left) reaches a target beyond the horizon by refracting off the ionosphere, and the echo signal from the target (right) returns to the receiving antenna by the same route. In practice, the beams are much closer to the horizon ...
Radar range and wavelength can be adapted for different surveys of bird and insect migration and daily habits. They can have other uses too in the biological field. "MERLIN Avian Radar System for Bird Activity Monitoring and Mortality Risk Mitigation" (PDF). Insect radar. Surveillance radar (mostly X and S band, i.e. primary ATC Radars)
The radar horizon is a critical area of performance for aircraft detection systems, defined by the distance at which the radar beam rises enough above the Earth 's surface to make detection of a target at the lowest level possible. It is associated with the low elevation region of performance, and its geometry depends on terrain, radar height ...
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The pulse width ( ) (or pulse duration) of the transmitted signal is the time, typically in microseconds, each pulse lasts. If the pulse is not a perfect square wave, the time is typically measured between the 50% power levels of the rising and falling edges of the pulse. The pulse width must be long enough to ensure that the radar emits ...