FIELD: physics.
SUBSTANCE: analysed electrical signal is time sampled and its discrete sample values are measured, wherein before measurement, the interval of controlled frequencies which includes the spectrum of the analysed signal is broken down to frequency resolution elements, the size of which is determined by the required accuracy of spectral analysis; the time sampling frequency of the signal is selected based on the ease of measurement; a weighting matrix is formed using the size of the resolution element and the sampling frequency; measured sample values of the analysed signal are merged into a vector; a vector-matrix equation of measurements is constructed and the spectrum of the analysed signal is determined therefrom in form of a vector whose components represent estimates of resolution element sampled spectrum components of the analysed signal.
EFFECT: wider range of analysed frequencies and possibility of reducing requirements for the response speed of the analogue-to-digital converters used.
