Patent ID: 9724016
Date: 2017-08-08
CPC Classifications: A61B

Claim:
1. A method of calculating respiratory rates, the method comprising: receiving, by a processor, an acoustic signal from an acoustic respiratory sensor coupled with a medical patient; estimating, by the processor, first respiratory rates from the acoustic signal using a first frequency domain representation of the acoustic signal; estimating, by the processor, second respiratory rates from the acoustic signal using a second frequency domain representation of the acoustic signal, the second frequency domain representation of the acoustic signal derived from samples of the acoustic signal sensed over a longer period of time than samples of the acoustic signal used to derive the first frequency domain representation of the acoustic signal; calculating, by the processor, first confidence values associated with the first respiratory rates based at least in part on a comparison between first harmonic energy and first total energy in frequency spectrums of the first frequency domain representation of the acoustic signal, the first harmonic energy comprising energy of one or more harmonics in the frequency spectrums; calculating, by the processor, second confidence values associated with the second respiratory rates based at least in part on a comparison between second harmonic energy and second total energy in frequency spectrums of the second frequency domain representation of the acoustic signal, the second harmonic energy comprising energy of one or more harmonics in the frequency spectrums; generating, by the processor, a point cloud including the first respiratory rates and the second respiratory rates; selecting, by the processor, overall respiratory rates from the first respiratory rates and the second respiratory rates based at least in part on comparisons between the first confidence values and the second confidence values and comparisons between trends in the first respiratory rates in the point cloud and trends in the second respiratory rates in the point cloud; and outputting, by the processor, the overall respiratory rates to a display for presentation on the display; wherein at least some of the same set of samples of the acoustic signal are used to estimate the first respiratory rates and the second respiratory rates and to calculate the first confidence values and the second confidence values.