A Portable and Affordable Photoplethysmography (PPG)-Based Health Monitoring Solution for Low-Resource Settings

Rose Sadiki Lyimo & Ally Ngulugulu
Department of Electrical Engineering, Arusha Technical College, Tanzania
Email: rose.sadiki1914@gmail.com

Abstract: This study presents the design and implementation of a real-time, cost-effective health monitoring system using Photoplethysmography (PPG) technology. The system aims to address the limitations of access to healthcare diagnostics in low-resource settings by providing a portable, affordable solution for continuous monitoring of vital physiological parameters. The proposed system utilizes a neonatal/adult PPG sensor equipped with red (660 nm) and infrared (940 nm) LEDs in a transmission configuration to capture pulse signals through the fingertip. The electrical output from the photodetector is processed through a transimpedance amplifier and digitized via an Arduino Uno microcontroller. Signal filtering and physiological parameter extraction—including heart rate, respiration rate, and oxygen saturation (SpO₂)— are performed using MATLAB. Wireless data transmission is enabled by an HC-05 Bluetooth module, allowing seamless remote monitoring via smartphones or computers. Comparative testing with a commercial pulse oximeter demonstrated a strong correlation in readings, validating the system’s accuracy. This approach significantly enhances access to primary diagnostic tools in rural healthcare environments, potentially reducing morbidity from cardiovascular and respiratory diseases. The project also outlines opportunities for system enhancement through IoT integration and dual-stage amplification for higher signal fidelity.