A SIMPLE AND NOVEL INTEGRATED OPTO-ELECTRONIC SYSTEM FOR BLOOD VOLUME PULSE SENSING AND HEART RATE MONITORING

A high sensitivity, low power, low cost sensor has been developed for sensing the blood volume pulse using transmission mode photoplethysmography (PPG) from the finger tip. It uses standard light emitting diode (LED) and phototransistor as emitter and detector, respectively. The sensor probe head is made of a material called delrin which is an acetal polymer having high dimensional stability and biocompatibility. A peripheral interface controller (PIC) microcontroller is used for the implementation of the measurement protocol. The wavelet denoising algorithm is used to suppress the noise component in the PPG signal. For heart rate (HR) estimate comparison, PPG signals are evaluated by comparing their beat-to-beat estimates with the corresponding R-R intervals from an electrocardiogram (ECG). The main advantages of the proposed approach are the reduction in cost, dimensions and power consumption. The probe can be well tolerated by the subject and is self-contained and portable.