US 12,257,101 B2
System and method for determining cardiac rhythm and/or respiratory rate
Alexis Martin, Montreal (CA); and Jeremie Voix, Montreal (CA)
Assigned to ECOLE DE TECHNOLOGIE SUPERIEURE, Montreal (CA)
Appl. No. 16/612,622
Filed by ECOLE DE TECHNOLOGIE SUPERIEURE, Montreal (CA)
PCT Filed Apr. 13, 2018, PCT No. PCT/CA2018/050453
§ 371(c)(1), (2) Date Nov. 11, 2019,
PCT Pub. No. WO2018/205013, PCT Pub. Date Nov. 15, 2018.
Claims priority of provisional application 62/504,258, filed on May 10, 2017.
Prior Publication US 2020/0196977 A1, Jun. 25, 2020
Int. Cl. A61B 5/00 (2006.01); A61B 5/024 (2006.01); A61B 7/00 (2006.01); A61B 7/04 (2006.01); G16H 50/20 (2018.01); G16H 50/30 (2018.01)
CPC A61B 7/04 (2013.01) [A61B 5/02444 (2013.01); A61B 5/7203 (2013.01); A61B 5/725 (2013.01); A61B 7/003 (2013.01); G16H 50/20 (2018.01); G16H 50/30 (2018.01)] 8 Claims
OG exemplary drawing
 
1. A computer-implemented method for determining an attribute of a heart rate or breathing rate, the method comprising:
capturing at least one inner audio signal inside an at least partially occluded ear canal with an in-ear microphone of an earpiece worn in the occluded ear canal of an active user;
capturing an outer audio signal with an outer-ear microphone of the earpiece, the outer audio signal being indicative of sounds captured from the environment outside the ear canal;
using an adaptive filter to compute an estimated residual signal of the environment present in the occluded ear canal using the outer audio signal;
denoising the at least one inner audio signal based on the estimated residual signal; and
using a processing device to determine a measurement of at least one of a heart rate and a breathing rate based on the denoised inner audio signal by extracting at least one of the heart rate and the breathing rate from the at least one inner audio signal, the extraction further comprising:
applying a first band pass filter on the at least one inner audio signal;
applying a Hilbert transform to extract the envelope of the filtered inner audio signal;
calculating ratios between one or more maxima of the spectrum of the extracted envelope;
determining a center frequency of a second band pass filter from the calculated ratios;
applying the second band pass filter on the filtered audio signal to produce a filtered signal; and
extracting the peaks of the filtered signal.