Aliasing: Difference between revisions

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{{Term
 
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|Meaning=#The introduction of [[error]] in the [[Fourier analysis]] of a discrete sampling from continuous  data, by which frequencies too high to be analyzed with the discrete sampling interval erroneously  contribute to the [[amplitude]] of the lower frequencies.
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|Explanation=Aliasing can be avoided by [[filtering]] out the high frequencies (using slower-response instruments  or analog electronic circuits) before sampling or digitizing. <br/>''See also'' [[Nyquist frequency]].<br/>  
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#In [[radar]], [[sodar]], and [[lidar]], the [[folding]] of [[target]] returns from outside the [[normal]] unambiguous  [[range]] interval ([[range folding]]) into the normal range interval, or the folding of [[radial velocity|radial  velocity]] measurements outside the [[unambiguous velocity interval]] ([[velocity folding]]) into the  normal velocity interval.
== aliasing ==
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#<div class="definition"><div class="short_definition">The introduction of [[error]] in the [[Fourier analysis]] of a discrete sampling from continuous  data, by which frequencies too high to be analyzed with the discrete sampling interval erroneously  contribute to the [[amplitude]] of the lower frequencies.</div><br/> <div class="paragraph">Aliasing can be avoided by [[filtering]] out the high frequencies (using slower-response instruments  or analog electronic circuits) before sampling or digitizing. <br/>''See also'' [[Nyquist frequency]].</div><br/> </div>
#<div class="definition"><div class="short_definition">In [[radar]], [[sodar]], and [[lidar]], the [[folding]] of [[target]] returns from outside the [[normal]] unambiguous  [[range]] interval ([[range folding]]) into the normal range interval, or the folding of [[radial  velocity]] measurements outside the [[unambiguous velocity interval]] ([[velocity folding]]) into the  normal velocity interval.</div><br/> </div>
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Latest revision as of 22:09, 27 March 2024

  1. The introduction of error in the Fourier analysis of a discrete sampling from continuous data, by which frequencies too high to be analyzed with the discrete sampling interval erroneously contribute to the amplitude of the lower frequencies.

Aliasing can be avoided by filtering out the high frequencies (using slower-response instruments or analog electronic circuits) before sampling or digitizing.
See also Nyquist frequency.

  1. In radar, sodar, and lidar, the folding of target returns from outside the normal unambiguous range interval (range folding) into the normal range interval, or the folding of radial velocity measurements outside the unambiguous velocity interval (velocity folding) into the normal velocity interval.
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