A Continuous Opto-Electronic Sensor for Blood Pressure Monitoring With Real-Time System

A new continuous wireless opto-electronic blood pressure (BP) sensor is successfully developed by this study. The BP device introduces the principle of photoplethysmograph (PPG) to sense the change of intravascular blood volume and calculate the BP. The real-time system adopts a LEDs of red/infrared light with a wavelengths of 660 and 905 nm. The analog front-end (AFE) circuit contains a pre-amplifier, a band-pass filter, a programmable gain amplifier (PGA), a microprocessor and a wireless module. A mobile phone is also used to display continuous BPs and record statistical analysis/results for users. The passband of filter is from 0.3 to 7.2 Hz. The PGA of adjustable gain are 8 channel. As results, 10 subjects in the experimental validation, in which the obtained BPs are compared with the results from a commercial BP monitor by OMRON. The maximum error of experimental results is ± 6 mmHg, which is less than ±8 mmHg conforming to the requirement by the Advancement of Medical Instrumentation (AAMI).