I don't have background knowledge about signal processing before and new at Matlab too.

I have EEG data (with noise removed) 1x128; sampling rate = 128 Hz, It's means that I have 1 sec. data right?

OK, I need to extracted to 5 frequency bands that are Delta (0-4 Hz), Theta (4-8 Hz), Alpha (8-16 Hz), Beta (16- 32 Hz) and Gamma (32-64 Hz) by Wavelet Transform (using Matlab), What is/are function--commands should I use?

And then, I need to compute the power spectrum (PSD) for each band, What is/are function--commands should I use?


Input: X = [1:128] and I need
Output: Y = [psdOfDelta, psdOfTheta, psdOfAlpha, psdOfBeta, psdOfGamma]


  • $\begingroup$ i have the same problem and i do not know how to use wavelet or FFT to get power spectrum density, so please i need help. $\endgroup$
    – user7854
    Feb 10, 2014 at 17:12
  • 1
    $\begingroup$ @shereen I used this method mathworks.com/matlabcentral/answers/… $\endgroup$
    – 1407522
    Mar 10, 2014 at 17:03

1 Answer 1


You need to do 1-Dimensional wavelet package decomposition. Here is the matlab documentation for the command to do this.

Here is some example code based on what you've described above:

wpt = wpdec(X, 2, 'db1', 'shannon')

This will provide a nice clickable graph. As you'll see in the documentation, you can provide a lot of different parameters for the decomposition.


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