Compact Circularly Polarized Implantable Antenna With Wide Axial-Ratio Bandwidth for biomedical applications

This work presents a compact circularly polarized (CP) implantable antenna operating at the 2.45 GHz industrial, scientific, and medical (ISM) Band. The antenna is etched on a top layer of a high permittivity substrate Rogers RT 6010 and it features very good miniaturization with overall dimensions of π× 3.5 2 × 0.5 mm3. To mimic the human body environment, the antenna was studied in a numerical three-layer phantom with an implant depth of 15 mm. The simulated results show that the antenna provides a good performance; an impedance bandwidth of 140 MHz (5.66%), a wide axial ratio (AR) bandwidth of 590 MHz (23%), and a peak gain of −26.25 dB were obtained, respectively. Furthermore, for health safety considerations, the specific absorption rate (SAR) was also investigated. All these characteristics make the presented antenna a promising candidate for implantable healthcare applications.