Medical and Biological Engineering and Computing

, Volume 28, Issue 6, pp 544–549 | Cite as

Noise reduction in biological step signals: application to saccadic EOG

  • I. N. Bankman
  • N. V. Thakor
Physiological Measurement


A weighted filter for noise reduction in nonrecurrent step signals where adaptive filtering cannot be applied is described. An optimal correction of a conventional finite impulse response (FIR) filter is achieved by using a priori knowledge of noise variance and a continuous estimation of the error signal's power. The weighted filter provides an optimal compromise between noise filtering and distortionless tracking. The prior knowledge required is that of the noise power and the lowest frequency in the noise spectrum. Application of the weighted filter to the saccadic electro-oculogram (EOG) results in better estimations of saccade duration and velocity.


EOG Filtering Noise reduction Saccade 


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Copyright information

© IFMBE 1990

Authors and Affiliations

  • I. N. Bankman
    • 1
  • N. V. Thakor
    • 1
  1. 1.Department of Biomedical EngineeringJohns Hopkins School of MedicineBaltimoreUSA

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