A Review of Wearable ECG System Design and Key Technologies

Abstract

Wearable electrocardiogram (ECG) monitoring has attracted increasing attention as cardiovascular diseases remain a major global health concern and long-term physiological monitoring is shifting from clinical settings to daily life. Despite recent advances in wearable healthcare technologies, reliable and low-power ECG acquisition remains challenging due to the low amplitude of biopotential signals, motion-induced artifacts, common-mode interference, and strict energy constraints. Many existing studies focus on individual components, such as electrodes, analog front-ends, or wireless communication modules, while system-level interactions and design trade-offs are less frequently addressed. This paper reviews the key engineering considerations involved in wearable ECG system design from a system-level perspective. The discussion covers the characteristics of ECG biopotentials and the evolution of electrode technologies, weak-signal acquisition and conditioning techniques in analog front-ends, Σ-Δ analog-to-digital conversion for narrow-band ECG signals, and commonly used wireless communication approaches for long-term monitoring. In addition, architectural trade-offs between distributed and integrated hardware implementations are discussed. Overall, this review aims to provide a coherent overview of how different design choices jointly influence performance, robustness, and energy efficiency in wearable ECG systems.