
80 Practical Biomedical Signal Analysis Using MATLAB
R
The matrix S( f ) contains auto-spectra of each channel on the diagonal and cross -
spectra off the diagonal. The simple rule connecting the model order with the number
of spectral peaks does not hold in the case of MVAR. Usually the model order is
lower, since there are more coefficients to describe spectral properties; their number
is equal k
2
p.
3.3 Measures of directedness
3.3.1 Estimators based on the phase difference
In the study of biomedical signals a problem of particular interest is finding the
direction of the influence exerted by one channel on the others, or in other words
finding the directedness. ...