Development of a low cost heart rate monitoring and transmission system using PPG signal processing for wearable devices

Abstract

Photoplethysmography (PPG) technique is used in most of the fitness tracking devices available now-a-days, due to its low cost and simplicity. These PPG signals are obtained from the variations in the blood flow with the help of pulse rate sensor. In this paper, PPG signal is acquired from two PPG sensors worn in the finger and the wrist to get the heart rate and its various parameters. The signal noise is removed with the help of MATLAB with various filters to get the smooth signal. The peak detection is done for heart rate (HR) and peak interval calculation, the spectral estimation is done, the first and second derivatives and the heart rate variability are obtained. The low cost Arduino nano and the Bluetooth module is used for the development and the transmission of HR value from the wearable device through an application developed for it, as well as the values are transmitted remotely with the help of the Global System for Communication (GSM) built in the mobile phone, which can display the value and can also transmit it to any particular person or remote physician who can monitor the person’s HR remotely. The complete system developed provides a low cost solution for heart rate detection and monitoring of a person from a distance.