Eigenvector based spatial filtering of fetal biomagnetic signals
-
M. Chen
, R. T. Wakai and B. Van Veen
Abstract
In this paper we demonstrate the usefulness of an eigenvector based spatial filtering method for signal processing of multi-channel fetal magnetocardiogram (fMCG) and fetal magnetoencephalogram (fMEG) recordings. This method of filtering can separate signal and interference by exploiting the considerable spatial information contained in multi-channel recordings. Typically, fMCGs and fMEGs suffer from large cardiac interference and low signal-to-noise ratio. To isolate the signal from the interference, we identify their respective subspaces using one portion of the record dominated by the signal and another dominated by the interference. Each subspace is approximately rank two since the sources of the signal and interference can be modeled as current dipoles. The spatial filter consists of a linear transformation that preserves the signal subspace and annihilates the interference subspace. It is easier to implement than a matched filter, preserves the morphology and topography of the fetal signal, and effectively removes maternal cardiac interference, even when the maternal and fetal complexes overlap strongly in time or when small maternal movements or maternal arrhythmias alter the temporal character of the interference.
Copyright © 2001 by Walter de Gruyter GmbH & Co. KG
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- Author Index
- Subject Index
- Contents
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- Incidence of meconium aspiration syndrome in term meconium-stained babies managed at birth with selective tracheal intubation
- Predicting preterm delivery and lowering very preterm delivery rate
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- Effect of labor on maternal dehydration, starvation, coagulation, and fibrinolysis
- Changes in light-induced fluorescence of cervical collagen in guinea pigs during gestation and after sodium nitroprusside treatment
- Cardiotocography or Doppler in making delivery decision?
- Book review
- Congress Calendar
Articles in the same Issue
- Author Index
- Subject Index
- Contents
- Fetal and maternal energy metabolism during labor in relation to the available caloric substrate
- Incidence of meconium aspiration syndrome in term meconium-stained babies managed at birth with selective tracheal intubation
- Predicting preterm delivery and lowering very preterm delivery rate
- Comparative effects of chronic exposure to glucose or sodium butyrate on surfactant development in fetal rabbits
- Eigenvector based spatial filtering of fetal biomagnetic signals
- Localization and quantification of adhesion molecule expression in the lower uterine segment during premature labor
- Is intrapartum vibroacoustic stimulation an effective predictor of fetal acidosis?
- Plasma adrenomedullin levels in pregnancies with appropriate for gestational age and small for gestational age infants
- Tissue concentrations of cytokines in the lower uterine segment during preterm parturition
- Effect of labor on maternal dehydration, starvation, coagulation, and fibrinolysis
- Changes in light-induced fluorescence of cervical collagen in guinea pigs during gestation and after sodium nitroprusside treatment
- Cardiotocography or Doppler in making delivery decision?
- Book review
- Congress Calendar