Galvanic Coupling Channel Characterization for Wearable Devices

Galvanic Coupling (GC) Intra-Body Communication offers a promising solution for reliable, low-power data transmission in wearable medical devices. However, signal performance is highly sensitive to electrode material and skin-electrode interface properties. This study uses finite element modeling (FEM) to quantify the effects of electrode design, including material choice, conductive gel, and foam layers, on the GC channel frequency response (CFR), focusing on attenuation, phase delay, and group delay. Results show that incorporating gel and foam significantly enhances signal transmission by reducing attenuation, minimizing phase distortion, and stabilizing group delay across a broad frequency range. These improvements help mitigate performance disparities between Ag/AgCl and copper (Cu) electrodes, supporting the development of high-performance, energy-efficient intra-body networks for wearable healthcare applications.