Design and implementation of a wearable real-time ECG monitoring system based on smartphone

Abstract

This research paper presents a smart approach for design and implementation of a wearable system that is able to monitor the electrical activity of the heart of a person using a smartphone. The real-time ECG monitoring system is implemented using a FPGA IC, a smartphone, and a front-end amplifier circuit for amplifying the ECG signal, and other component includes a capacitor, comparator, and a register. A USB link of PHY/LINK 1.1 and delta modulator is implemented in the digital circuit block of the FPGA IC. The digital block for the delta modulator consist of a sinc filter, a sampler basically a D flip-flop, and a FIR filter. Clock frequency at which sampler works is 6 MHz, delta modulator takes the input voltage in the 0.25–1.25 V @ up to 1.75 kHz frequencies, and it generates a corresponding 8-bit code @ 23.5 kS/s. The FPGA IC and all other circuits are powered by a smartphone through a micro USB link and provide a power supply of DC 5 V. In our system, we have used the screen of the smartphone as a display device and the captured ECG is displayed on the smartphone. For the calculation of the heart rate of the captured ECG signal, we used the smartphone and the result with waveform is stored in the memory of smartphone.