Segmentation and tracking of the electro-encephalogram signal using an adaptive recursive bandpass filter



An adaptive filtering approach for the segmentation and tracking of electro-encephalogram (EEG) signal waves is described. In this approach, an adaptive recursive bandpass filter is employed for estimating and tracking the centre frequency associated with each EEG wave. The main advantage inherent in the approach is that the employed adaptive filter has only one unknown coefficient to be updated. This coefficient, having an absolute value less than 1, represents an efficient distinct feature for each EEG specific wave, and its time function reflects the non-stationarity behaviour of the EEG signal. Therefore the proposed approach is simple and accurarate in comparison with existing multivariate adaptive approaches. The approach is examined using extensive computer simulations. It is applied to computer-generated EEG signals composed of different waves. The adaptive filter coefficient (i.e. the segmentation parameter) is −0.492 for the delta wave, −0.360 for the theta wave, −0.191 for the alpha wave, −0.027 for the sigma wave, 0.138 for the beta wave and 0.605 for the gamma wave. This implies that the segmentation parameter increases with the increase in the centre frequency of the EEG waves, which provides fast on-line information about the behaviour of the EEG signal. The approach is also applied to real-world EEG data for the detection of sleep spindles.


Electro-encephalogram analysis Non-stationarity Adaptive tracking of centre frequency of biomedical signals 


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© IFMBE 2001

Authors and Affiliations

  1. 1.Laboratory for Advanced Brain Signal Processing, Brain Science InstituteRIKENSaitamaJapan
  2. 2.Assiut UniversityAssiutEgypt
  3. 3.Warsaw University of TechnologyWarsawPoland

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