The main objective of this thesis project is to implement a wireless vital signs monitoring systemfor measuring the ECG of a patient in the home environment. The research focuses on two specificresearch objectives: 1) the development of a distributed healthcare system for vital signsmonitoring using wireless sensor network devices and 2) a practical test and performanceevaluation for the reliability for such low-rate wireless technology in ubiquitous health monitoringapplications.

The first section of the thesis describes the design and implementation of a ubiquitoushealthcare system constructed from tiny components for the home healthcare of elderly persons.The system comprises a smart shirt with ECG electrodes and acceleration sensors, a wirelesssensor network node, a base station and a server computer for the continuous monitoring of ECGsignals. ECG data is a commonly used vital sign in clinical and trauma care. The ECG data isdisplayed on a graphical user interface (GUI) by transferring it to a PDA or a terminal PC. Thesmart shirt is a wearable T-shirt designed to collect ECG and acceleration signals from the humanbody in the course of daily life.

In the second section, a performance evaluation of the reliability of IEEE 802.15.4 low-ratewireless ubiquitous health monitoring is presented. Three scenarios of performance studies areapplied through practical tests: 1) the effects of the distance between sensor nodes and base-station, 2) the deployment of the number of sensor nodes in a network and 3) data transmissionusing different time intervals. These factors were measured to analyse the reliability of thedeveloped technology in low-rate wireless ubiquitous health monitoring applications.

The results showed how the relationship between the bit-error-rate (BER) and signal-to-noiseratio (SNR) was affected when varying the distance between sensor node and base-station, throughthe deployment of the number of sensor nodes in a network and through data transmission usingdifferent time intervals.