Electrocardiogram Measurement during Sleep with Wearing Clothes Using Capacitively-Coupled Electrodes

The electrocardiogram (ECG) was measured by non-contact, non-restraint and unconscious method using capacitively-coupled electrodes made of electro-conductive cloth while subjects lay on bed wearing their clothes. These electrodes are very sensitive so measure not only signals but noise. The seat grounded, which arranged under the electrode could suppress noise. Two types of electrode different in length were used, that is long type and short type. Results showed that both electrodes could sense ECG. Noise generated from e.g. commercial power source was almost the same for both electrodes though the length of electrode was longer than the subject for the long type electrode. Setting position was rather serious and noise component changed greatly by the part of body that touches the electrode. Next, ECG was measured on these condition participants lay with supine position, prone position, right lateral position and left lateral position. The ECG was measured on each condition.