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Apparent frequency

The one frequency in [0,f_s/2] that a reconstruction from aliased samples will actually produce.

The apparent frequency of a sampled signal is whichever of its infinitely many aliases lies in [0,f_s/2] -- the single value any reconstruction built purely from the samples will produce, regardless of which true frequency in that family actually generated them.

Examples

  • Samples taken at f_s=8 samples/s from a 7 Hz tone show an apparent frequency of 1 Hz.

See also

Aliasing
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