Design of a Compact Implantable Antenna in Seven-layer Brain Phantom for Brain-machine Interface Applications

This paper presents an inset-fed meandered shape radiating patch antenna for biotelemetry at ISM band. Biocompatible alumina (
$\epsilon r=9.4$
and
$tan\delta=0.0004$
) is used as substrate and for top and bottom isolation layer. The antenna is constructed with defected ground structure (DGS) and a shorting pin. The entire construction is placed between cortical bone and dura layer of seven-layer human brain phantom to characterize its performance in transmitting neural signal to the external machine or computer as an application in brain-machine interface technology. The antenna resonates at the frequency of 2.404 GHz with a relatively compact volume of 30.03 mm
³
. It also exhibits better input impedance and bandwidth of
$48.87+\mathrm{j}\ 0.27\ \Omega$
and 19.16%, respectively.