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A pulse-Doppler radar is a radar system that determines the range to a target using pulse-timing techniques, and uses the Doppler effect of the returned signal to determine the target object's velocity.
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.
A plan position indicator (PPI) is a type of radar display that represents the radar antenna in the center of the display, with the distance from it and height above ground drawn as concentric circles. As the radar antenna rotates, a radial trace on the PPI sweeps in unison with it about the center point. It is the most common type of radar ...
Pulse-Doppler radar and Continuous-wave radar are required for high performance in this area because these exclude low-velocity reflections. This is a critical measure of performance for the Littoral zone and land-based radar. Prevailing winds of about 15 mile/hour cover most of the surface of the earth. This constantly stirs up debris into the ...
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.
GPR depth section (profile) showing a single line of data from the survey of the historic crypt shown above. The domed roof of the crypt can be seen between 1 and 2.5 meters below surface. The concept of radar is familiar to most people. With ground penetrating radar, the radar signal – an electromagnetic pulse – is directed into the ground.
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.
Radar pulses diverge as they move away from the radar station. Thus the volume of air that a radar pulse is traversing is larger for areas farther away from the station, and smaller for nearby areas, decreasing resolution at farther distances. At the end of a 150 – 200 km sounding range, the volume of air scanned by a single pulse might be on ...