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The National Imagery Interpretability Rating Scale (NIIRS) is an American subjective scale used for rating the quality of imagery acquired from various types of imaging systems. The NIIRS defines different levels of image quality/interpretability based on the types of tasks an analyst can perform with images of a given NIIRS rating.
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 ...
A full-waveform Light Detection And Ranging (LiDAR) system has the ability to record many returns per emitted pulse, as a function of time, to reveal the vertical structure of the illuminated object, showing position of the individual targets, and finer details of the signature of intercepted surfaces or the proportion of the canopy complexity ...
Lidar (/ ˈ l aɪ d ɑːr /, also LIDAR, LiDAR or LADAR, an acronym of "light detection and ranging" [1] or "laser imaging, detection, and ranging" [2]) is a method for determining ranges by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver.
where P(r) is the power of the backscattered radiation received by the lidar telescope in distance r, E is transmitted laser-pulse energy, L is the lidar constant summarizing its optical and detection characteristics, O(r) is the overlap function, [21] and / and / are the aerosol/molecular backscatter- and extinction coefficient respectively.
Lidar pulses used for remote sensing get pulse echoes off the ground and off clouds. When there is a layer of broken clouds at the top of the boundary layer, IPDA lidar techniques used for atmospheric composition remote sensing can obtain the boundary layer composition.
A commonly used radar or sonar pulse is the linear frequency modulated (LFM) pulse (or "chirp"). It has the advantage of greater bandwidth while keeping the pulse duration short and envelope constant. A constant envelope LFM pulse has an ambiguity function similar to that of the square pulse, except that it is skewed in the delay-Doppler plane ...
Pulse compression is a signal processing technique commonly used by radar, sonar and echography to either increase the range resolution when pulse length is ...