Wearable Continuous Blood Pressure Estimation with Photoplethysmography Sensors Array on the Arm

A wearable continuous beat-to-beat blood pressure (BP) monitoring system on the arm, based on a 4-channel photoplethysmography (PPG) array is presented in this paper. Three pulse transit time (PTT) values have been derived from the combinations of PPG signals from the sensors array. We evaluated the system on a group of 5 healthy male subjects. The result suggests that there is a strong correlation between the pulse wave velocity (PWV) derived from PPG signals of the sensors array and the reference systolic and diastolic BP. With the PPG-sensor array, PWV along the arm is divided into several segments. Therefore, more detailed PWV along the arm is found, which can potentially facilitate the accuracy of estimating BP based on the PWV principle.