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Updated: Oct 15, 2025

Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters
Published on: February 4, 2018
Design of a tunable turnstile mode converter for high-power microwave applications
Xiaoyu Wang1, Yuwei Fan1, Baoping Yang2
1College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China.
Abstract:
This study investigates the frequency tunability of a coaxial transverse electromagnetic mode (TEM)-linear-polarized TE11 mode tunable turnstile mode converter (TTMC) for high-power microwave applications using a combination of simulation and experiment. In the proposed structure, the sliding folded waveguide can be moved radially to meet the requirement of linear polarization, and the matching structure is designed to eliminate the undesired reflection. The simulation shows that the conversion efficiency of the TTMC can reach over 99% in the frequency range of 1.45-2.35 GHz, corresponding to a frequency tuning bandwidth of about 47.4%. Moreover, the TTMC can maintain a continuous high conversion efficiency at different frequency points by changing the tuning mechanism. The experimental investigation shows that the TTMC can convert the coaxial TEM mode into a circular waveguide TE11 mode with a conversion efficiency of above 95% in the frequency range of 1.55-2.35 GHz. The experimental measurements agree well with the simulation results, implying feasibility of the TTMC design and its superior performance.
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