Verily Life Sciences LLC

Christopher Towles Lengerich

Mark Murphy

Russell N Mirov

Ali Shoeb

Raphael Cendrillon

Systems and methods are provided for determining the frequency of a cardiovascular pulse based on a first physiological signal that is continuously available and a second physiological signal that is less available and that is more accurate or otherwise improved relative to the first signal with respect to pulse rate estimation. When the second signal is available it controls the determination of the pulse rate. When the second signal is unavailable, the first signal is used to determine the pulse rate. This can include using the first signal to estimate the pulse rate until the second signal is available, at which point the pulse rate is estimated based on the second physiological signal. Alternatively, the first signal could be used to determine a number of candidate pulse rates, and the second signal could be used to select a pulse rate from the set of candidate pulse rates.

Method for improving heart rate estimates by combining multiple measurement modalities

Systems and methods are provided for determining the frequency of a cardiovascular pulse based on a photoplethysmographic measurement of blood in a portion of subsurface vasculature. A plurality of samples of the photoplethysmographic signal are obtained and a frequency spectrum determined based on a first set of the plurality of samples. A frequency is determined based on a maximum frequency component of the frequency spectrum. Further, a confidence level of the determined frequency of the maximum frequency component is determined based on the magnitude of the maximum frequency component and the overall energy in the frequency spectrum. A pulse rate is then determined by updating a predicted pulse rate of a second, earlier set of the plurality of samples based on the frequency of the maximum frequency component and the determined confidence level.

Method for improving accuracy of pulse rate estimation

Systems and methods are provided for determining a pulse rate based on a photoplethysmographic measurement of blood in a portion of subsurface vasculature. A plurality of samples of the photoplethysmographic signal are obtained and a plurality of digital phase-locked loops are operated to generate respective oscillating signals based on the plurality of samples. Respective correlations between the plurality of samples and each of the generated oscillating signals are determined and used to select a subset of the plurality of phase-locked loops. The frequencies of the selected oscillating signals generated by the selected phase-locked loops are determined and used to determine a cardiovascular pulse rate. This method can be performed a plurality of times for a respective plurality of overlapping sets of the obtained plurality of samples to determine pulse rates over time.

Growing community of inventors

Palo Alto, CA, United States of America

Christopher Towles Lengerich