Fig. 2: Examples of the sensor outputs and estimated RV, RR, and HR.
From: Wearable radio-frequency sensing of respiratory rate, respiratory volume, and heart rate
a, b The normalized BIOPAC chest-belt signals (a) and normalized unfiltered NCS signals (b) showing respiration waveforms during tidal (normal) breathing. The NCS thorax signal shows strong heartbeat motion as well. c The PTM airflow signal with detected inspiration and expiration start points. d The extracted instantaneous volume \({\mathrm{Vol}}_{{\mathrm{PTM}}}\) (dotted green) from the airflow, and calibrated chest belts (blue) and NCS (dashed-dotted red) respiration volume waveforms. e–g The analysis of the data shown in a and b; e and f show RV and RR, respectively, from NCS and BIOPAC chest belts; g shows the HR from NCS and BIOPAC ECG.
