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2025-12-17
Frequency- and Phase-Tunable Coupler Based on Three-Line and Four-Line Coupled Lines
By
Progress In Electromagnetics Research C, Vol. 163, 113-119, 2026
Abstract
This paper proposes a reconfigurable 3-dB coupler with tunable phase and frequency characteristics based on triple-line loaded varactor diodes. The core structure employs a four-line coupling configuration to ensure strong coupling characteristics and stability. Through integrated theoretical analysis and experimental verification, the coupler demonstrates a center frequency tuning range of 1.8-2.4 GHz with continuous phase difference adjustment from 40° to 140°. Measured results indicate that high isolation (> 20 dB) and low return loss (< -20 dB) can be obtained.
Citation
Bo Huang, Yongle Wu, Shuchen Zhen, Weimin Wang, and Jinchun Gao, "Frequency- and Phase-Tunable Coupler Based on Three-Line and Four-Line Coupled Lines," Progress In Electromagnetics Research C, Vol. 163, 113-119, 2026.
doi:10.2528/PIERC25091906
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