Spectral analysis device for the optimal estimation of the autospectrum of a signal of the cross spectrum of the two signals and its application to the estimation of an interspectral matrix

摘要

The signals coming from source 10 are converted into digital form 14 and undergo a fourier transform in order to obtain their frequency transforms. The processing circuit 20 is arranged to calculate the log - periodogram of a signal and the two signals interpériodogramme. The means 24 provide the smoothing of the log - periodogram or interpériodogramme by calculation of a weighting window optimum. The estimated interspectra autospectres and are obtained after smoothing. By using a recursive algorithm comprising of the estimations of autospectres and interspectra, a set of signals can be decorrelated, and bleached, leading to the estimation of the interspectral matrix. The present invention finds a particular application in the processing of signals electroencephalographic, in particular for the map in the brain, the location of the sources of cerebral activity and the search for the relationships between those -.