The algorithm for pulse measurement using a human’s and fetus’s phonocardiogram without classifying heart sounds

The relevance of the research is due to the prospects of phonocardiogram employment for daily monitoring of a fetus’s and mother’s state by designing inexpensive portable devices. Currently, there are no software and hardware systems that completely solve this problem. In this regard, the article presents the algorithm for pulse measurement by means of a phonocardiogram for signal processing in the streaming mode. The algorithm feature is a human’s and fetus’s pulse measurement based on the heart sound segmentation without classifying them into the first and second heart sounds, as well as detecting them under the conditions of other physiological and mechanical sounds, absence of one of the heart sounds in the signal, and deviations in the segmented sound boundaries from the actual localization of the cardiovascular system. For assessing the credibility of the results, the pulse values, obtained by the developed algorithm and reference methods, were compared. The pulse values, calculated by two experts with the aid of a phonocardiogram, were used as a standard for comparison. The average relative deviation between the findings and the reference method results does not exceed 3 %. The article materials are of practical value for the design of a fetus and human state daily monitoring systems.

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