A Low-Profile Implantable Antenna for Heart Implants

The complex nature of the human body and the interaction between implantable antennas and electronic components can result in detuning issues. A wide bandwidth is critical for mitigating these issues and improving channel capacity. This paper presents a compact implantable antenna that provides ultra-wide bandwidth for leadless cardiac pacemakers (LCPs). The proposed antenna has an ultra-compact size of 8.33 mm³, with a 10-dB bandwidth of 4.33 GHz (fractional bandwidth of 152.7%), spanning from 0.67 to 5 GHz. It covers the Industrial, Scientific, and Medical (ISM) bands (0.915 GHz and 2.45 GHz), the Wireless Medical Telemetry Service (WMTS) band (1.4 GHz), and the midfield band (1.6 GHz). Simulation results demonstrate gains of −31.3 dBi at 0.915 GHz, −25.8 dBi at 1.4 GHz, and −21.9 dBi at 2.45 GHz. This antenna exhibits peak Specific Absorption Rate (SAR) values of 320.4 W/kg at 0.915 GHz, 332.8 W/kg at 1.4 GHz, and 464.1 W/kg at 2.45 GHz. To ensure the reliability of the wireless communication link, the link budget is analyzed to estimate the range between the transmitter and receiver at data rates of 10 and 25 Mbps. To validate the results, the manufactured antenna is tested with minced pork, demonstrating a satisfactory agreement between the measured and simulated outcomes.