Evaluating QoS of a Wireless System for Real-Time Cardiac Monitoring

Quality of service (QoS), and in particular reliability and low latency, are essential qualities of safety-critical wireless systems for medical applications. However, wireless links are typically prone to bursts of errors, with characteristics which vary over time. We propose a wireless system suitable for real-time remote patient monitoring in which both the necessary reliability and a bounded end-to-end delay are achieved by an efficient error control scheme. We have paired an example electrocardiography (ECG) application to this wireless system. We also developed a tool chain to assess various combinations of system parameters: we can determine the QoS in terms of the packet-delivery ratio and the end-to-end latency, and also the size of jitter buffer required for seamless ECG monitoring services. A realistic assessment, based on data from the MIT-BIT arrhythmia database, shows that the proposed wireless system can achieve an appropriate level of QoS for real-time ECG monitoring if link-level error control is appropriately implemented.