Modeling of a capacitive link for data telemetry to biomedical implants

Abstract

This paper presents modeling of a capacitive link for wireless data transfer to implantable biomedical microsystems. Based on the proposed model, voltage transfer ratio of the link is calculated, and its most important parameters are highlighted.To validate the suggested model, measurements are performed with 5 mm × 5mm plates, which have a layer of chicken breast with 3.5 mm thickness in between. Comparison between experimental results and model-based simulations shows that the model can be used for characterizing capacitive links.

Implantable Biomedical Devices

“…One of the most important advantages of the capacitive coupling over its inductive counterparts is the high-pass nature of the link. As a result, high voltage transfer ratios can be achieved even when the transmitted signal contains wide range of harmonics, like digital data and BPSK signals [81].…”

“…The dielectric of this capacitor is mostly the body tissue between the plates. A detailed model of this type of capacitance and the complete capacitive link can be found in [81]. One of the most important advantages of the capacitive coupling over its inductive counterparts is the high-pass nature of the link.…”

“…Recently, employing capacitive links for implantable biomedical applications was studied in [80,81]. The idea of capacitive coupling has been already used for inter-chip data communication [82] and power transfer [83], and also for sensing biomedical signals [84,85].…”

A New Design of Capacitive Power Transfer Based on Hybrid Approach for Biomedical Implantable Device

“…Some implantable device types require a biosafety source of electrical power to operate properly. The sealed battery as the power source of implantable devices can only supply the energy for a limited time [6]. The patient will experience trauma with repeated surgery for replacing the battery.…”

“…The capacitive wireless power transfer, on the other hand, has been used in several applications and has been proposed for biomedical implantable device since 2009 by Amir M. Sodagar et. al [2][3][4][5][6][7][8][9][10][11]. This approach was also recently used for sensing the biomedical signal as given in [12].…”