Purpose: Capacitive-based sensors have become prominent in physiological sig- nal measurement over the past decade. The electrical characteristics of the capacitive electrode depend on various parameters.
Methods: In this work, we proposed a Capacitive Electrode (CE) with optimal Shielding and Guarding design (SGD). The gold was coated over the copper on the base material FR4 is used for electrode material. Three different designs were proposed. The performance of each design was evaluated using the Finite Element Method (FEM).
Results: On comparing all the electrophysical parameters of the three designs, the design: ”The shielding was designed in such a way that it conversed with the electrode, and the guarding was formed as a concentric around the sensing plate” shows optimal SGD, which enables higher performance. The proposed electrode was applied for the ECG application. The optimal electrodes (OE) were placed in the lead I and V1 V2 lead positions. The experimental results conducted by Finite Element Method (FEM) show that the lead I position is the optimal lead position for ECG measurement. The developed Capacitive electrodes were tested to fetch the ECG signal. When comparing the proposed electrode with the traditional 12-lead ECG system and the AD8232 sensor, the SNR value shows better signal quality for the proposed electrode.
Conclusion: This research mainly concentrates on the electrical characteristics of the capacitive electrodes with optimal shielding and guarding design. The proposed capacitive electrode can also used to fetch other bio-signals.