Method and system for evaluating the quality of ratio of ratios values
AssigneeBiosency
InventorsGurvan Priem, Quentin Bodinier
Life of this patent
Estimating the term…
Abstract
A method intended for the evaluation of the quality of ratio of ratios (RR) values computed for at least two photoplethysmographic (PPG) signals corresponding to distinct wavelengths, each PPG signal including successive heartbeat patterns. The method includes the steps of: segmenting the PPG signals into a plurality of signal segments each corresponding to one heartbeat pattern; for each given signal segment, computing a sequence of RR values; and evaluating, for each given signal segment, a quality index of the sequence of computed RR values on the basis of a computed heart rate and/or a measured peripheral temperature corresponding to the given signal segment.
Claims14
A computer-implemented method for evaluating quality of ratio of ratios, RR, values computed for at least three photoplethysmographic, PPG, signals corresponding to distinct wavelengths, wherein each PPG signal comprises successive heartbeat signal segments, said method comprising:
- segmenting a first PPG signal corresponding to a red wavelength and a second PPG signal corresponding to an infrared wavelength into a plurality of signal segments each corresponding to one heartbeat, by:
- extracting a sequence of heartbeat instants tb,g[n] from a third PPG signal corresponding to a third wavelength;
- segmenting the first and second PPG signals into a plurality of signal segments, each signal segment corresponding to one heartbeat, using the sequence of heartbeat instants tb,g[n] extracted from the third PPG signal,
- for each given signal segment, computing a sequence of RR values, and
- evaluating, for each given signal segment, a quality index of the sequence of computed RR values on the basis of a computed heart rate and/or a measured peripheral temperature corresponding to the given signal segment.
A method for evaluating an SpO2 value based on a ratio of ratios, RR, value evaluated according to the method of any one of the preceding claims, wherein the photoplethysmographic, PPG, signals are obtained by using LEDs as light sources, the SpO2 value being obtained using a calibration model having as parameters the RR value and the LED current of at least one of the LEDs.
A system for evaluating the quality of ratio of ratios, RR, values computed for at least three photoplethysmographic, PPG, signals corresponding to distinct wavelengths, wherein each PPG signal comprises successive heartbeat, said system comprising:
- a segmentation module for segmenting a first PPG signal corresponding to a red wavelength and a second PPG signal corresponding to an infrared wavelength into a plurality of signal segments each corresponding to one heartbeat pattern,
- a computation module for computing, for each given signal segment, a sequence of RR values, by:
- extracting a sequence of heartbeat instants tb,g[n] from a third PPG signal corresponding to a third wavelength;
- segmenting the first and second PPG signals into a plurality of signal segments using the heartbeat patterns extracted from the third PPG signal, and
- an evaluation module for evaluating, for each given signal segment, a quality index of the sequence of computed RR values on the basis of a computed heart rate and/or a measured peripheral temperature corresponding to the given signal segment.
Dependencies are inferred from the claim text.