A High-Efficiency Microwave Power Combining System Based on Frequency-Tuning Injection-Locked Magnetrons

• Published in: IEEE transactions on electron devices Vol. 67; no. 10; pp. 4447 - 4452
• Main Authors: Chen, Xiaojie, Yang, Bo, Shinohara, Naoki, Liu, Changjun
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.10.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Efficiency; Energy utilization; Ferrites; Injection-locking; Magnetrons; Microwave attenuation; Microwave communication; Microwave devices; phase control; power combining; Time-frequency analysis; Tuning; Wave attenuation; Waveguides
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2020.3013510

To increase the power level and energy utilization rate of injection-locked magnetron sources, a dual-way 1-kW <inline-formula> <tex-math notation="LaTeX">{S} </tex-math></inline-formula>-band magnetron microwave power combining system with high combining efficiency was proposed and validated. A waveguide magic-Tee was used to achieve power combining and to provide a pathway for the reference signal. This system utilizes the power-dividing characteristic of a magic-Tee to lock two magnetrons. Frequency tuning is applied to adjust the phase difference between the two magnetrons' signals so as to achieve a high combining efficiency. Experimental results indicate that the microwave power combining efficiency of the proposed system reaches 94.5%. The attenuation of microwave power is caused only by the waveguides and magic-Tee. Our investigation provides a guideline for future high-power microwave combining systems with low losses.