A Miniaturized Dual-Band Implantable Antenna With Low SAR for Biomedical Multi-Scenario Applications

This letter proposes a miniaturized dual-band implantable antenna specifically designed for Implantable Medical Devices (IMD) with multi-scenario implantation requirements, which addresses the critical challenges of miniaturization, multi-scenario application, and low specific absorption rate (SAR). This antenna operates at 1.4 and 2.45 GHz frequency bands, with a compact volume of approximately 14.36 mm³ (π × 3² × 0.508 mm³) and a reduced radiation area of 28.27mm² (a 56.2% reduction).It is designed with a planar slot structure on the substrate, and optimized via electromagnetic simulation based on a ten-layer brain model and a three-layer muscle model. Experimental verification in a minced pork model and a brain phantom model shows that the impedance bandwidth is 174 MHz (12.43%) at 1.4 GHz and 252 MHz (10.29%) at 2.45 GHz, with reflection coefficients below -20 dB. SAR assessment confirms its compliance with safety standards. This antenna is suitable for applications such as arteriovenous graft monitoring and cortical visual prosthesis data transmission.