The theorem of Shannon-Nyquist says that when sampling a signal, no frequency component of that signal should be greater than half the samplerate. Frequencies that exceed this so-called Nyquist frequency will not be sampled correctly, but instead re-appear in the signal as aliasing-components.They will fold over the sampling frequency: one hertz above the sampling frequency will become one Hertz below, 500 above will become 500 below and so on.Ja.x wrote:Never mind pronountiation? Will someone explain me what aliasing is?Someone (who cares?) wrote:alley-ay-sing
ay-lee-us-ing![]()
(Maybe we call it some other thing in my native language, you know...)
To avoid this, a lowpass filter is applied to the signal before it is sampled to make sure all frequencies above the Nyquist frequency are suppressed...