METHOD OF MEASURING HEART RATE IN FETUS Russian patent published in 2013 - IPC A61B8/02 G06F17/00 

FIELD: medicine.

SUBSTANCE: invention relates to field of medicine. In method realisation probing by means of ultrasound signal, directed to area of fetus heart location, is carried out. Reflected Doppler signal is amplified and converted into digital form. Ultrasonic irradiation signal represents series of pulses, where frequency of their repetition equals carrier frequency of ultrasonic signal and is determined depending on maximal depth of probing. Amplification of signal is first performed in frequency band, consistent with duration of series of irradiation with discretisation frequency, corresponding to band of received signal. Transfer of Doppler signal spectrum on zero frequency and accumulation of complex signal counts in accordance with position and size of measured volume by probing depth are performed. Filtration of Doppler signal in specified frequency band is carried out. Search for peaks of autocorrelation function is carried out and distance between them is determined. Doppler shift is calculated on the basis of calculation of difference of phases between Doppler signals from successive series of ultrasound signal. Width of spectrum of Doppler frequencies and energy of Doppler signal from all sections of probing depth are evaluated. After that, control of parameters of Doppler signals from entire probing depth is performed, for which purpose separation of sections of probing depth, related to fetal heartbeats is carried out on the basis of the analysis of parameters of spectrum of Doppler frequencies. After that, adaptive reception gate for signal of fetal heartbeats is formed, in accordance with which the following corrected ultrasound signal is formed.

EFFECT: invention makes it possible to increase accuracy of frequency of heart rate in fetus by automatic setting of position and value of measurement Doppler volume in accordance with fetus heart position by probing depth.

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