Investigation of the curvature distribution for TE₀₁-to-TM₁₁ mode converter

Abstract

An oversized TE${}_{01}$-to-TM${}_{11}$ mode converter based on waveguide bend structure is designed for high power transmission line. The curvature distribution of the waveguide bend is analyzed and optimized using mode coupling theory. Analysis results show that the curvature near the output port plays a decisive role in the content of the parasitic modes, which indicates that the restriction on curvature far from output port could be relaxed. Therefore, the asymmetric waveguide axis with enhanced curvature near the front end and lessened curvature near the output port will have a high conversion efficiency and a broad bandwidth. Combining the curvature optimization and the phase rematching technology proposed in our preliminary work, the TE${}_{01}$-to-TM${}_{11}$ mode converter realizes a 90${}^{\circ }$ bend with a conversion efficiency over 95% in the range of 26–32.2 GHz (the relative bandwidth over 21%). To verify the designed mode converter, a prototype is manufactured and measured.

Keywords:

• Curvature distribution
• high power transmission line
• millimeter-wave
• mode converter
• waveguide bend

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China under Grant 610054,61921002.

Notes on contributors

Xiaoyi Liao

Xiaoyi Liao received the B.S. degree in 2015 and the Ph.D. degree in 2020 from the University of Electronic Science and Technology of China, Chengdu, China, and now he is engaged as an associate professor by the Nanjing University of Information Science and Technology, Nanjing, China.

Zewei Wu

Zewei Wu received the Ph.D. degree from the University of Electronic Science and Technology of China, Chengdu, China, in 2015. He is currently with the School of Electronic Science and Engineering, University of Electronic Science and Technology of China. His current research interests include high-power microwave components, antennas, and numerical simulations in electromagnetic engineering.

Minxing Wang

Minxing Wang received the B.S. degree from the University of Electronic Science and Technology of China, Chengdu, China, in 2018, where he is currently pursuing the Ph.D. degree. His current research interests include high-power microwave propagation and quasi-optical components.