Nyquist rate

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Image:Bandlimited.png In signal processing, the Nyquist Rate is the minimum sampling rate (in samples per second) required to avoid aliasing when sampling a continuous signal. If the input signal is real and bandlimited, the Nyquist rate is simply twice the highest frequency contained within the signal. In other words, the Nyquist rate is equal to the two-sided bandwidth of the signal.

<math>f_N = 2 f_H \,</math>

where <math>f_H \,</math> is the highest frequency component contained in the signal.

To avoid aliasing, the sampling rate must exceed the Nyquist rate:

<math>f_S > f_N \,</math>

See also