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<DIV style="FONT: 10pt arial">----- Original Message -----
<DIV style="BACKGROUND: #e4e4e4; font-color: black"><B>From:</B> <A
title=tininmartinez@gmail.com href="mailto:tininmartinez@gmail.com">Martin
Martinez</A> </DIV>
<DIV><B>To:</B> <A title=eeglablist@sccn.ucsd.edu
href="mailto:eeglablist@sccn.ucsd.edu">eeglablist@sccn.ucsd.edu</A> </DIV>
<DIV><B>Sent:</B> Friday, November 21, 2008 8:00 PM</DIV>
<DIV><B>Subject:</B> Central Frequency Estimation</DIV></DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2>Good evening,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I am working on EEG signals in PSGs. Once i filter
the EEG signal with the correct low pass filter, i take some parameters of the
signal to work with. One of this parameters is dominant rythm or central
frequency. To estimate this, I make the FFT of the portion of signal and then i
calculate the centroid. After that, I plot the evaluation of the central
frequency along the EEG signal. My problem is that I think that the central
frequency is 1-2 Hz higher that I hope and my question is if anyone knows
another methods or related info on the matter.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Alter that, I tried an AR-2 model of the signal and
the average of central frequency decreases, but if i try to make it with the EMG
signal, the behavour changes...</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Can anyone help me with this 'Central Frequency
Estimation' in EEGs?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thank you very much,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Martin</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>P.S.: I apply before notch filters to eliminate DC
signal, and contribution of low-frequency is very little (so the spectrum seems
correct).</FONT></DIV></BODY></HTML>