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High PRF is limited to systems that require close-in performance, like proximity fuses and law enforcement radar. For example, if 30 samples are taken during the quiescent phase between transmit pulses using a 30 kHz PRF, then true range can be determined to a maximum of 150 km using 1 microsecond samples (30 x C / 30,000 km/s).
The received signals are also compared using the frequency ambiguity resolution process. A blind velocity occurs when Doppler frequency falls close to the PRF. This folds the return signal into the same filter as stationary clutter reflections. Rapidly alternating different PRF while scanning eliminates blind frequencies.
Temporal resolution (TR) is the precision of a measurement with respect to time. Movie cameras and high-speed cameras can resolve events at different points in time. The time resolution used for movies is usually 24 to 48 frames per second (frames/s), whereas high-speed cameras may resolve 50 to 300 frames/s, or even more.
The difference between the sample numbers where reflection signal is found for these two PRF will be about the same as the number of the ambiguous range intervals between the radar and the reflector (i.e.: if the reflection falls in sample 3 for PRF 1 and in sample 5 for PRF 2, then the reflector is in ambiguous range interval 2=5-3).
For magnifying computer graphics with low resolution and few colors (usually from 2 to 256 colors), better results will be achieved by pixel art scaling algorithms such as hqx or xbr. These produce sharp edges and maintain high level of detail.
Most digital cinema is displayed in 2K or 4K resolution; 2K is only a small amount more resolution than the consumer-oriented 1080p HD format. [ 15 ] High-profile film directors such as Christopher Nolan , [ 16 ] Paul Thomas Anderson [ 17 ] and Quentin Tarantino have all publicly criticized digital cinema and digital cinematography , and ...
At full resolution, this image has clearly visible compression artifacts, for example along the edges of the rightmost trusses. Sharpness determines the amount of detail an image can convey. System sharpness is affected by the lens (design and manufacturing quality, focal length, aperture, and distance from the image center) and sensor (pixel ...
Ground targets further than this range cannot be detected, so the PRF can be quite high; a radar with a PRF of 7.5 kHz will return ambiguous echoes from targets at about 20 km, or over the horizon. If however, the PRF was doubled to 15 kHz, then the ambiguous range is reduced to 10 km and targets beyond this range would only appear on the ...