Electromagnetic interactions between biological tissues and implantable biotelemetry systems

Biotelemetry which provides wireless communication links between internal devices and outside equipment is a promising function for future implantable biomedical devices. In order to build reliable wireless links, detailed characterization and performance evaluation of the telemetry links are required. In this work, the finite difference time domain (FDTD) simulations are performed to analyze the radiation performances of small dipole and loop antennas in biological tissues for various biotelemetry links. By comparing the electrical characteristics of vertical and horizontal loop antennas above a perfect electric conductors (PEC) plane, the effects of biomedical devices on biotelemetry links are estimated in terms of radiation efficiency and specific absorption rate (SAR). Finally, it is observed that electromagnetic band-gap (EBG) structures are useful candidates for biotelemetry link design.