The Acquisition and Application of ECG in Wearable Devices

Electrocardiogram (ECG) is a technique that captures electric signals existing in the body. After the amplification, a waveform representing heart functions would be generated for observations. Based on the analysis of its waveform, ECG played an important role in cardiac diagnosis. But the formal ECG is time-consuming, which indicates it may not be appliable in emergencies. As such, ECG on the wearable device is the best solution for diagnoses in emergencies that could generate the waveform as soon as possible or even warn the patient before the emergency. But the ECG needs to match a standard of accuracy that any tiny abnormal waveform may result in miscellaneous diseases. This requires a clear signal captured by ECG and lowers the noise gained in the amplification circuit. With the improvement in the technology, many types of wearable ECG devices appeared in the market with their own identity. This paper focused on certain techniques and the applicability of the device. Specifically, the ECG equipped on the wearable devices was introduced here from the perspective of the waveform, circuit amplifier, and current application. This work also gave an in-depth discussion about these techniques to provide an insight into the development of the wearable ECG.