Gain Enhancement of a Compact Implantable Dipole for Biomedical Applications

Abstract

A new compact implantable planar dipole with an enhanced gain performance and a relatively low specific absorption rate (SAR) is proposed. In the proposed dipole, a part of each arm is shaped as a folded meander-line structure, especially designed to have a minimal size and cover the medical device radio communications service band (MedRadio, 401–406 MHz). It is shown that using this technique, the gain of the antenna can be increased without compromising miniaturization. The antenna has a peak realized gain of −23.7 dBi and its total volume is 20 mm3. The antenna has a relatively low SAR, so that the maximum transmitting power satisfying the regulatory limitation is 7.7 dBm. The SAR simulation results are confirmed experimentally.