Welch method vs fft

1. Why is Welch method better?
2. What are the main advantages of using the Welch method instead of the traditional periodogram?
3. What is the difference between PSD and FFT?
4. How does Welch method work?

Why is Welch method better?

8.3.

One reason Welch's method improves upon Student's T is that under random sampling, Welch's method satisfies the basic requirement of converging to the correct answer as the sample sizes get large when randomly sampling from nonnormal distributions, even when the sample sizes are unequal.

What are the main advantages of using the Welch method instead of the traditional periodogram?

Welch's method is an improvement on the standard periodogram spectrum estimating method and on Bartlett's method, in that it reduces noise in the estimated power spectra in exchange for reducing the frequency resolution.

What is the difference between PSD and FFT?

The PSD and FFT are tools for measuring and analyzing a signal's frequency content. The FFT transfers time data to the frequency domain, which allows engineers to view changes in frequency values. The PSD takes another step and calculates the power, or strength, of the frequency content.

How does Welch method work?

The Welch method reduces the variance of the periodogram method by averaging. This method first divides a time series into overlapping subsequences by applying a window to each subsequence and then averaging the periodogram of each subsequence.