Nyquist Frequency

In order to recover all Fourier components of a periodic waveform, it is necessary to sample twice as fast as the highest waveform frequency $\nu$,

$$f_{\rm Nyquist} = 2\nu.$$

The minimum sampling frequency is called the Nyquist frequency.

See also Fourier Series, Fourier Transform, Nyquist Sampling, Oversampling, Sampling Theorem