28.4 A battery-powered efficient multi-sensor acquisition system with simultaneous ECG, BIO-Z, GSR, and PPG

This paper reports a battery-powered, multi-parameter recording platform with built-in support for concurrent ECG, Bio-Impedance (BIO-Z), Galvanic Skin Response (GSR) and Photoplethysmogram (PPG). The expanded list of dedicated sensor modalities provides a more accurate, more reliable and broader health assessment in wearable electronics. Since data is collected on one chip, precise synchronization between data streams is possible, allowing to use correlation techniques between the data streams. It supports, e.g., research on blood pressure estimation by combining ECG and PPG measurements through pulse arrival time analysis. Combining different sensing modalities like ECG, PPG, and BIO-Z can result in better estimation of hemodynamic parameters, as well as heartbeat and heart-rate variability.