Simulation and Calibration Device of Synchronous Blood Pressure and Reflectance Photoplethysmographic Signals

Photoplethysmography (PPG) based noninvasive blood pressure (BP) measurements need calibration frequently. But the existing blood pressure calibration methods could not offer synchronous PPG and BP signals simultaneously. There are only indirect calibration methods based on other BP measurement devices as an alternate. A simplified method is proposed and a device is developed to simulate the heart pumping, BP generation and pulse propagation physically. The device can produce a simulated systolic BP ranged from 50 to 430 mmHg and two reflectance PPG sensors at different sites can record the simulated blood volume changes synchronously. A quadratic regression analysis is performed to test this device, and the results show that the pulse arrival time (PAT) measured from the simulated PPGs has a quadratic relationship with the synchronously produced BP. It accords with the physiological features of human circulatory system. The device can be used for simulation and calibration of PPG-based BP measurements.