Numerical modeling of the aortic and pulmonary component of the second tone signal and application of the Wigner — Ville transform for processing the obtained model signal for the purpose of component separation are performed. If the components can be separated in the time-frequency domain with use of Wigner-Ville transform, it is possible to restore their temporal profile by overlaying the corresponding mask and performing the inverse transformation. It is shown that the components of the second tone can be separated with a time delay exceeding 40 ms. Signals of the second tone of the human heart were recorded with a stethoscope connected to a microphone. Acoustic signals were filtered by a hardware filter with a tunable cutoff frequency in the range of 31-125 Hz and processed using Wigner — Ville transform. In norm, when the delay between aortic and pulmonary components does not exceed 30 ms, their separation by the proposed method is impossible.
$^1$MSU, Faculty of Physics
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