Basic FAQ for FFT Analyzer

Anti-aliasing filter is a low-pass filter designed to prevent aliasing (folding) errors that may occur during sampling. Since the highest frequency contained in the input signal (f m) is usually unknown, when performing frequency analysis with an FFT analyzer, the sampling frequency f s is determined, and the power of frequency bands above 1/2 f s is sufficiently attenuated by the aforementioned low-pass filter before sampling. This frequency of 1/2 f s is called the Nyquist frequency.

	3.5 Sampling Theorem (Regarding FFT Analyzer)