PMMA based ultra miniaturized implantable antenna for biotelemetry applications

Recent advancement in engineered biomedical materials has facilitated breakthroughs in the field of the medical world. Poly (Methyl Methacrylate) PMMA is explored as a promising biocompatible substrate for an implantable antenna, whose dielectric properties are experimentally characterised before antenna design, ensuring realistic performance evaluation in biological tissues. This paper proposes a PMMA-based compact miniaturised implantable antenna of size 38.4 mm³ for the wireless medical telemetry service (WMTS) band operating at 1.4 GHz. The proposed antenna can be implanted either in the skin or the muscle. The gain of the antenna is -17.93 dBi and -28.15 dBi in the skin and muscle tissue, respectively, with a specific absorption rate (SAR) of less than 1.6 Watts/kg. The performance characteristics of the fabricated prototypes are verified by implanting them in human tissues, emulated phantom models of skin and muscle, which are observed to be in line with the simulated results. Finally, a robust link budget is established for biotelemetry applications in the indoor short-range communication system, based on certain constraints (power limitation, SAR, and frequency).