Wireless ECG measurement system with capacitive coupling

This paper describes a measurement system that captures an electrocardiogram (ECG) using capacitively coupled electrodes. The measurement system was integrated into an off-the-shelf office chair (so-called Aachen SmartChair). Whereas for classical ECG measurement adhesive is used to attach conductively coupled electrodes to bare skin, the system presented allows ECG measurement through clothing without direct skin contact. Furthermore, a ZigBee (TM) communication module was integrated to allow wireless transmission of ECG data to a PC or an ICU patient monitor. For system validation, classical ECG using conductive electrodes was obtained simultaneously. First measurement results, including variations of cloth thickness and material, are presented and some of the system-specific problems of this approach are discussed.