Automatic Signal Appraisal for Unobtrusive ECG Measurements

This paper focuses on facilitating ECG-measurements in our daily life. When measuring ambulatory ECG, the trade-off between signal quality and sensor comfort is obvious. Unobtrusive measurement systems do not achieve the same level of signal quality as systems using conventional wet ECG electrodes. To enable automatic ECG analyses, a continuous appraisal of the signal quality is essential. The presented work describes a method to transform the problem of appraising the quality of an ECG signal into a two-class classification problem. We therefore define an appropriate quality label and train a logistic regression model to predict the signal quality of an ECG signal. We show the working principle using a contactless ECG system incorporated into an airplane seat. The system is evaluated with twelve subjects performing airplane passenger activities. A correct signal quality appraisal rate of 92% is achieved in a leave-one-person-out cross-validation.