RF Rectifier Design for Efficient WPT in Medical Implants: A Wideband Approach for White Space WiFi and LTE Applications

This paper presents a unique design approach for a high-efficiency wideband RF rectifier, which incorporates a two-branch cell configuration combined with an L-shunt matching network (MN), a radial stub, and a series inductor. The rectifier has been optimized to achieve peak power transfer efficiency across the 2.37–2.70 GHz frequency range, making it well suited for white space Wi-Fi and LTE applications. Simulation results indicate promising performance, with a maximum power conversion efficiency (PCE) of 66.25% at an input power level of 5 dBm. Furthermore, the rectifier achieves RF-to-DC conversion efficiencies between 11.50% and 13.5% at -20 dBm, demonstrating its effectiveness across a range of input power levels. Designed on an RT/Duroid substrate, the rectifier has a compact footprint of 19.75 mm × 15.20 mm and utilizes a single-series diode (SSrd) architecture. The design employs a sequential matching technique to ensure a wide impedance bandwidth, enabling efficient utilization of the targeted frequency spectrum. This work highlights the potential of the proposed rectifier for wireless power transfer applications in biomedical implants, particularly in scenarios where ambient power management is critical.