Dual-band rectenna system for biomedical wireless applications

Abstract

- This paper proposes a dual-band RF energy harvester to power biomedical wireless devices for various health applications. Biomedical devices may be implantable medical devices or wearable devices. The proposed system's novelty is that it can work in widespread operating power ranges with good conversion efficiencies. The Pi impedance matching network is used in the projected dual-band rectifier that is practicable for RF energy harvesting within the existing band of frequencies. The proposed antenna is simulated and designed using CST MW Studio 2018, while for the designing and simulation of the rectifier, ADS 2020 is used. Also, for the DC pass filter and matching network, ADS 2020 is used. For fabrication, an FR-4 lossy substrate having a dielectric constant of 4.4 and dielectric height of 1.6 mm is used. The projected result shows that the conversion efficiency is greater than 50% (capable of 78%), with an input power range of 8.5–10 dBm. At an input power of 8 dBm, the typical DC voltage was increased to 1.8 V. With the use of matching circuits, the maximum conversion efficiency is 78%, while without a matching circuit, the maximum conversion efficiency is only 37%. The matching circuit was critical for conversion efficiency.