Calcolatore Risoluzione FFT — Formula
## The Nyquist-Shannon Sampling Theorem
To perfectly reconstruct a signal, you must sample at least twice the highest frequency present.
### Formula
**f_Nyquist = f_sample / 2**
Any signal component above the Nyquist frequency will alias (fold back) into the baseband, creating distortion. This is why anti-aliasing filters are placed before ADCs.
### Common Examples
- CD audio: 44.1 kHz sampling, 22.05 kHz Nyquist
- Phone: 8 kHz sampling, 4 kHz Nyquist
- Professional audio: 96 kHz sampling, 48 kHz Nyquist
To perfectly reconstruct a signal, you must sample at least twice the highest frequency present.
### Formula
**f_Nyquist = f_sample / 2**
Any signal component above the Nyquist frequency will alias (fold back) into the baseband, creating distortion. This is why anti-aliasing filters are placed before ADCs.
### Common Examples
- CD audio: 44.1 kHz sampling, 22.05 kHz Nyquist
- Phone: 8 kHz sampling, 4 kHz Nyquist
- Professional audio: 96 kHz sampling, 48 kHz Nyquist
Esempio Risolto
CD-quality audio at 44,100 Hz sampling rate.
- Nyquist frequency: 44,100 / 2 = 22,050 Hz
- In kHz: 22.050 kHz
- Sampling period: 1,000,000 / 44,100 = 22.676 microseconds