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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 ...
Radar transmission frequency spectrum of a trapezoid pulse profile Recent advances in signal processing techniques have made the use of pulse profiling or shaping more common. By shaping the pulse envelope before it is applied to the transmitting device, say to a cosine law or a trapezoid, the bandwidth can be limited at source, with less ...
The transmitters used in the SIRE radar are transversal electromagnetic (TEM) horns that generate short, 1 nanosecond-long radar pulses with a pulse repetition frequency (PRF) of 1 MHz and a frequency band from 300 to 2500 MHz. [7]
Radar is a system that uses radio waves to determine the distance (), 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.
Pulse Doppler radar may have 50 or more pulses between the radar and the reflector. Pulse Doppler relies on medium pulse repetition frequency (PRF) from about 3 kHz to 30 kHz. Each transmit pulse is separated by 5 km to 50 km distance. Range and speed of the target are folded by a modulo operation produced by the sampling process. True range is ...
Pulse-Doppler radar for aircraft detection has two modes. Scan; Track; Scan mode involves frequency filtering, amplitude thresholding, and ambiguity resolution. Once a reflection has been detected and resolved, the pulse-Doppler radar automatically transitions to tracking mode for the volume of space surrounding the track.
Ground-penetrating radar uses a variety of technologies to generate the radar signal: these are impulse, [48] stepped frequency, frequency-modulated continuous-wave , and noise. Systems on the market in 2009 also use Digital signal processing (DSP) to process the data during survey work rather than off-line.
ARSR-3 and 3D search radar were used by the FAA in the Joint Surveillance System (JSS). The radar operated in the L-band at 1250 to 1350 MHz and detected targets at distances beyond 210 nautical miles; 390 kilometres (240 mi). The D model had height-finder capability. Westinghouse also built ARSR-4 3-D air surveillance radar in the 1990s for ...