Methods for long-distance respiration rate measurement using noisy and irregularly sampled sensor signals

Abstract

A system for measuring long-distance respiration rate is provided. The system includes a processing unit configured to receive and normalized a sensor output signal. The processing unit is further configured to compute a series of four Discrete Prolate Spheroid window functions. For each of the series of four Discrete Prolate Spheroid window functions, the processing unit is configured to (1) multiply the normalized sensor output signal by the Discrete Prolate Spheroid window function to produce a windowed output signal, and (2) compute a Lomb-Scargle periodogram based on the windowed output signal. The processing unit is further configured to compute a weighted average of the Lomb-Scargle periodograms to produce an averaged periodogram. The processing unit is further configured to compute a frequency corresponding to a peak estimated spectral density on the averaged periodogram. The processing unit is further configured to output breaths per minute data based on the frequency.