Journal of Radio Electronics. eISSN 1684-1719. 2025. №11

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DOI: https://doi.org/10.30898/1684-1719.2025.11.35

COUPLED-LINE transDIRECTIONAL couplers

AND MICROWAVE circuits based on THEM. REVIEW

A.N. Sychev, S.A. Artishchev, N.S. Trufanova, N.Y. Rudy

Tomsk State University of Control Systems and Radioelectronics

634050, Russia, Tomsk, pr. Lenin 40

The paper was received September 15, 2025.

Abstract. The article presents the current state of research and development of directional couplers built on coupled lines with the transverse directivity effect, which have not received enough attention in domestic research to date. The use of transdirectional (TRD) couplers in the design of microwave circuits leads to new circuitry and original design and technological solutions. The considered applications include both microwave devices and beamforming circuits and their components. The classification of TRD couplers presented according to various criteria reflects their features, and above all, the galvanic isolation of the input port and a pair of output ports. The review reflects the current level of technology and reveals little-studied areas of research that are useful in creating new solutions for directional couplers on coupled lines and creating microwave devices based on them with unique characteristics.

Key words: transdirectional coupler, coupled lines, coupling coefficient, transformation coefficient.

Financing: This work was supported by the Russian Science Foundation under Grant No. 25-29-00316, https://rscf.ru/en/project/25-29-00316/.

Corresponding author: Sychev Aleksand Nikolaevich, ans@main.tusur.ru

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For citation:

Sychev A.N., Artishchev S.A., Trufanova N.S., Rudy N.Y. Coupled-line transdirectional couplers and microwave circuits based on them. Review // Journal of Radio Electronics. – 2025. – №. 11. https://doi.org/10.30898/1684-1719.2025.11.35 (In Russian)