Adaptive Filtering Technique and Comparison of PS25015A Dry Electrodes and Two Different Ag/AgCl Wet Electrodes for Wearable ECG Applications

The electrocardiogram (ECG) is one of the most important signals acquired from the body, as it serves as the immediate source of information relating to heart performance. Hence, a lot of research has gone into various types of ECG acquisition methods and systems. With the numerous methods and systems available at hand, it is important to compare, contrast, and evaluate the existing techniques. Not only does this help distinguish between the different techniques, it also helps build on the existing methods to create successful acquisition systems that can surpass the effect of unwanted factors, such as movement and other noise artifacts. This paper builds on a previous study that compared two different ECG acquisition systems, one of which uses PS25015A dry electrodes and the other, which uses two different silver/silver chloride (Ag/AgCl) wet electrodes. The adaptive filtering technique was implemented in order to test its effectiveness when applied to a wearable ECG medical device, intended to monitor the user’s ECG throughout daily activities, such as walking. According to statistical analysis, the dry electrodes may have a better SNR. However, the dry electrodes provided a lower wave amplitude, compared to the wet electrodes. Overall, the least mean squares (LMS) adaptive filtering, along with bandpass filtering, helped reduce motion artifacts in ECG signals acquired during walking. Copyright © 2015 IFSA Publishing, S. L.