Development of a Wireless Cardiogram System for acute and long-term healthcare monitoring

A wireless system to monitor patient's heart activities has been designed, implemented and tested. The system is designed for acute and long term monitoring of patients at homes, clinics, nursing homes, or rural health-care clinics. This system consists of a Phonocardiogram (PCG) unit, an Electrocardiogram (ECG) unit, and a receiving remote unit. The PCG and the ECG units are the sensing units that acquire and filter the corresponding heart signals and transmit them using the nRF24LE1 system on chip to the remote unit. The nRF24LE1 chip is an ultra low power wireless chip that has a microcontroller, an Analog to Digital Converter (ADC), and an antenna to transmit the data. The remote unit also contains an nRF24LE1 chip for receiving the signals and interfacing with a computer to store and view the received signals. After building the system, the microcontroller was programmed to perform the functions of digitizing, transmission, and receiving of the signals. The PCG and ECG analog signals, captured by oscilloscopes, were found to be real, accurate, and clean. The signals received by the remote unit placed at 100 feet away were compared with the analog signals. The results show that the two signals are almost identical. This means that this wireless system can provide accurate and continuous monitoring of patients within a 100-foot distance. This ensures that the system can be utilized within the space of a building whether it is a hospital, a clinic, a nursing home, or a private home.

I. Introduction

The ability to provide continuous monitoring of acutely sick patients in hospitals, residents of nursing homes, elders at homes, and patients at remote area clinics depends on the availability of reliable, low cost, portable wireless systems for heart monitoring. These systems would provide the patients with the needed care in their familiar environment, with fewer constraints and greater mobility [1]. The two main signals used to monitor the heart are those obtained from a Phonocardiogram (PCG) and an Electrocardiogram (ECG). PCG's record the heart sound, which provide information on the heart's mechanical activity and its valve integrity, while ECG's measure the electrical activity of the heart [2].