Frequency resolution of random process

4 vues (au cours des 30 derniers jours)
Raziur Rahman
Raziur Rahman le 11 Oct 2015
Commenté : Walter Roberson le 13 Oct 2015
I have got a random process with 100 samples. What frequency resolution can be obtained with traditional methods of Power Spectral Density calculation? How can I do this in matlab?

Réponses (2)

Image Analyst
Image Analyst le 11 Oct 2015
Have you tried using pwelch() or periodogram()?
  1 commentaire
Raziur Rahman
Raziur Rahman le 13 Oct 2015
I can pass the signal with this method. Then I have got a power spectrum density. Now what is frequency resolution?

Connectez-vous pour commenter.


Walter Roberson
Walter Roberson le 11 Oct 2015
Neither traditional methods nor MATLAB can obtain any frequency resolution based solely on 100 random samples. In order to obtain any frequency resolution, it is necessary for there to be times associated with each of the samples, as frequency has to do with change in time.
  2 commentaires
Raziur Rahman
Raziur Rahman le 13 Oct 2015
The signal is in time domain. If I calculate power spectrum density with different traditional method, then what is frequency resolution?
Walter Roberson
Walter Roberson le 13 Oct 2015
Question:
Let X = 0:0.01:100 . Let it be in the time domain. What is the frequency resolution of that X, using any method you want?
Answer: You cannot know based upon only that information.
Question: add the assumption that the times of the samples are
t = sort( rand(1,100) * 20 );
Answer:
Now you have a chance of determining the frequency resolution.
The frequency resolution is 1/2 of the lowest common multiple of the time differences diff(t) when expressed in rational form.

Connectez-vous pour commenter.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by