Howtosignalprocessing
- How do you calculate Nyquist frequency?
- What happens when you do not follow the Nyquist sampling theorem?
- What happens if the sampling frequency is less than the Nyquist limit?
- What happens if you sample at Nyquist frequency?
How do you calculate Nyquist frequency?
The frequency fn = 1/2Δt is called the Nyquist frequency. When spectra are presented for digital data, the highest frequency shown is the Nyquist frequency. For IRIS broadband seismic stations, Δt = 0.05 s, so the Nyquist frequency is 10 Hz.
What happens when you do not follow the Nyquist sampling theorem?
If the Nyquist theorem is not obeyed, higher frequency information is recorded in too low a sample rate, resulting in aliasing artifacts. Several techniques can reduce aliasing in a reproduced signal.
What happens if the sampling frequency is less than the Nyquist limit?
When the sampling frequency drops below the Nyquist rate, the frequencies will crossover and cause aliasing.
What happens if you sample at Nyquist frequency?
It can be seen that by sampling at the Nyquist rate, we can get the frequency information about the signal. However, to faithfully reconstruct the signal, we have to increase the sampling rate even more.
