High-Efficiency Long-Distance Wireless Power Transfer Using BaO and GaN Magnetron's Cathode

A magnetron is one of the most common microwave power generators used in commercial or industrial applications. There are a few methods for optimizing the magnetron to enhance its efficiency, which include the selection of the building materials, increasing the resonant cavity, enlarging operation space size, and modifying the anode structure. This article proposes the modification of magnetron cathode for high-frequency and low-power applications using gallium nitride (GaN)-coated cathode replacing the current barium oxide (BaO) coat. The highlighted optimization is intended to modify the control of magnetron electron drift velocity, heat dissipation, operation frequency, and power generation. Simulation and experimental results have been extracted at 2.45 GHz to generate 5 W microwave power and tested for over 30 ft. of power transmission using a rectenna interface, which results in an efficiency of 88.37%, compared with 51.8% using BaO coat.