Periodogram vs fft

1. What is periodogram FFT?
2. What's the difference between periodogram and spectrogram?
3. What is the purpose of a periodogram?
4. Should I use FFT or PSD?

What is periodogram FFT?

The Periodogram block estimates the power spectral density (PSD) or mean-square spectrum (MSS) of the input. The block uses the periodogram method and Welch's averaged, modified periodogram method. The block averages the squared magnitude of the FFT function computed over windowed sections of the input.

What's the difference between periodogram and spectrogram?

For a Periodogram , returns the computed power at each frequency as a Vector. For a Spectrogram , returns the computed power at each frequency and time bin as a Matrix. Dimensions are frequency × time.

What is the purpose of a periodogram?

A periodogram is used to identify the dominant periods (or frequencies) of a time series. This can be a helpful tool for identifying the dominant cyclical behavior in a series, particularly when the cycles are not related to the commonly encountered monthly or quarterly seasonality.

Should I use FFT or PSD?

FFTs are great at analyzing vibration when there are a finite number of dominant frequency components; but power spectral densities (PSD) are used to characterize random vibration signals.