US 12,453,484 B2
Maternal and fetal heart rate monitor
Dennis Matthews, Meadow Vista, CA (US); Xiaomeng Gao, Dublin, CA (US); Xiaonan Jiang, Davis, CA (US); Xiaoguang Liu, Davis, CA (US); Jeremy Thompson, Grange (AU); Kylie Dunning, Prospect (AU); Kenneth Pawlak, Reno, NV (US); and Chris Ryman, Crystal Bay, NV (US)
Assigned to THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, Oakland, CA (US)
Filed by THE REGENTS OF THE UNVIERSITY OF CALIFORNIA, Oakland, CA (US)
Filed on Jun. 9, 2021, as Appl. No. 17/343,364.
Claims priority of provisional application 63/036,678, filed on Jun. 9, 2020.
Prior Publication US 2021/0378532 A1, Dec. 9, 2021
Int. Cl. A61B 5/024 (2006.01); A01K 29/00 (2006.01); A61B 5/00 (2006.01); A61B 5/05 (2021.01)
CPC A61B 5/02411 (2013.01) [A01K 29/005 (2013.01); A61B 5/0011 (2013.01); A61B 5/02438 (2013.01); A61B 5/02444 (2013.01); A61B 5/05 (2013.01); A61B 5/6831 (2013.01); A61B 5/6867 (2013.01); A61B 2503/40 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A handheld pregnancy detection device comprising:
an antenna configured for placement adjacent to hair, dermis, or combination of hair and dermis of a non-human mammalian potentially pregnant subject;
a continuous wave (CW) Doppler radar transmitter electrically coupled to the antenna and configured to transmit electromagnetic (EM) signals via the antenna with sufficient power to penetrate between about 5 cm and about 50 cm of the dermis, muscle, bone, and body tissue of the subject to reach a heart of a fetus in the subject;
a radar receiver electrically coupled to the antenna and configured to receive EM signals, via the antenna, reflected from the fetus and that repenetrate between the about 5 cm and the about 50 cm of the dermis, muscle, bone, and body tissue of the subject, wherein mechanical contraction and expansion of the heart of the fetus creates a doppler shift that is modulated into reflected EM signals, wherein the received reflected EM signals have a signal to noise ratio sufficiently high to tolerate user induced hand motions of the handheld device and minute motions of the fetus, the reflected EM signals comprising raw in-phase and quadrature (I/Q) data that includes periodic frequency of motion data; and
a processor configured to:
segment the raw in-phase and quadrature (I/Q) data into data segments;
linearly detrend the data segments to identify I/Q data segments of interest;
process the data segments of interest to remove low-frequency drifting high frequency noise, and/or abrupt signal changes, and generate clean data segments;
demodulate the clean data segments to extract motion information and produce an extracted mixture motion profile that contains maternal heart rate (MHR), maternal respiration rate (MRR), and fetal heart rate (FHR) data;
bandpass filter and Fast Fourier transform the mixed motion profile to separate MHR and MRR data from FHR data; and
extract the FHR data, including the periodic frequency of motion data, as an indicator of fetal heart motion of the fetus.