Apparatus for evaluating selected signal parts in physiological signals, in particular for late potentials in electrocardiograms

摘要

The apparatus is distinguished by a recording which has a particularly low noise level and which also allows a single-beat analysis. To calculate frequency spectra, two autoregressive models, the maximum entropy method and adaptive filter determination are alternatively used. These algorithms are particularly adapted for use in electrocardiograms by means of new methods for calculating the optimum order of the autoregressive model. Referred to the possible frequency range of the signal sections to be investigated (for example late potentials), the area integral of spectra, recorded progressively with offset in time, for a frequency range of, for example, 40 Hz /= f /= 160 Hz are first calculated for some of the spectra and then for the remaining spectra and a normality factor is determined as the quotient of the summed area integrals of the first and second number of time segments examined, for determining the spectral contour. …IMAGE…