Design of a Loop Resonator with Improved Power Transmission Efficiency Using a Ferrite Plate

Abstract

We propose a novel resonator that can reduce magnetic field leakage using a ferrite plate. The proposed resonator consists of a rectangular loop, a ferrite plate, and an L-matching network. The ferrite plate is used as an H-field reflector to direct more H-field to each resonator, and the L-matching network is employed to match the 50 Ω of the feed cable at 13.56 MHz. Two identical resonators with dimensions of 30 cm × 15 cm are separated by 50 cm, and the resulting transmission efficiency is about −12.3 dB at 13.56 MHz. This is about 4.2 dB higher than the resonators without the ferrite plate.