L-band dual-frequency recirculating planar magnetron

ABSTRACT

Dual-frequency oscillators have been used in many technical disciplines on account of the phase correlation between two output signals or the feasibility of producing beat wave effect. The mechanism to generate two different-frequency microwave outputs from one magnetron was discussed and simulated. Strapping technique and phase velocity modulation were adopted to generate random frequency ratio and adequate output power. The relationship between phase velocity difference and total output power was investigated and the proper variation range of phase velocity difference was discussed. The conclusion above will accelerate the design flow of dual-frequency magnetron in various frequency demand. A method of optimal E/B distribution was also applied to reduce electron recirculating loss and obtained a notable power enhancement. To fulfill the demand of producing two microwave outputs with a desirable 3:4 frequency ratio in L-band, a conventional vacuum electronic device called Dual-Frequency Recirculating Planar Magnetron (DFRPM) was modeled. There was a significant difference between planar magnetron and cylindrical magnetron, one large shared planar cathode provided better thermal stability and separated the cavity into two slow-wave structures (SWSs), consequently, each SWS arose an oscillation at their own operating frequency. The primary frequencies of two output signals were at 1.30 GHz/1.70 GHz and overcame the frequency ratio limitation happened in other design scheme.

KEYWORDS:

• Dual frequency
• planar magnetron
• beat wave
• vacuum electronic

ORCID

Hao Zhou http://orcid.org/0000-0003-1718-3512

Additional information

Funding

This work was supported by National Natural Science Foundation of China: [Grant Number 60501013,60971035].

Notes on contributors

Hao Zhou

Hao Zhou received the M.S. and B.S. degrees in the University of Electronic Science and Technology of China. He is currently a doctoral student.

Tianming Li

Tianming Li received the B.S. degree in testing technology and instruments in 1996, the M.S. degree in physical electronics in 2001, and the Ph.D. degree in physical electronics in 2005, all from the University of Electronic Science and Technology of China, Chengdu, China. He is currently with at the School of Electronics Science and Engineering, University of Electronic Science and Technology of China. His current research activities include high-power microwave generation and wireless power transmission.

Shengen Li

Shengen Li (M’12) received the B.S. degree in communication engineering from Tianjin University, Tianjin, China, in 2006, and the M.S. degree in physical electronics from the Beijing Vacuum Electronics Research Institute (BVERI), Beijing, China, in 2009. He is currently a Staff Member with the Crossed Field Device Laboratory, BVERI, where he is also an engineer in magnetrons. His current research interests include cold cathode magnetrons, millimeter magnetrons, THz magnetrons, high-power magnetrons, and crossed field amplifier.