Journal of Radio Electronics. eISSN 1684-1719. 2024. ¹6

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Full text in Russian (pdf)

Russian page

 

 

DOI: https://doi.org/10.30898/1684-1719.2024.6.7

 

 

 

SYNTHESIS OF MODAL AND disTributed PARAMETERS

OF ASYMMETRIC COUPLED LINES

WITH INHOMOGENEOUS DIELECTRICS

 

A. N. Sychev

 

Tomsk State University of Control Systems and Radioelectronics

634050, Russia, Tomsk, pr. Lenin 40

 

The paper was received March 21, 2024.

 

Abstract. A technique for synthesizing asymmetrical coupled transmission lines with inhomogeneous dielectrics is proposed, which consists in choosing working physically based modal parameters from which the primary parameters – per-unit-length capacitance and inductance – are calculated. Three impedance parameters are taken as a basis (characteristic impedance, transformation and coupling coefficients), one of the modal voltages and a pair of modal dielectric constants. All selected for synthesis initial data have known ranges of acceptable values and a clear physical meaning. Previously little-studied features and interdependencies of parameters, including impedance and phase, were investigated. To demonstrate the technique capabilities, synthesized numerical values of the modal and distributed parameters of the original 3-dB hybrids are presented. The results can be useful in developing new coupled line designs and creating microwave devices with unique characteristics based on them.

Key words: coupled lines, modal voltages, modal parameters, per-unit-length capacitance, per-unit-length inductance, transformation ratio, coupling coefficient, characteristic impedance.

Financing: The work was carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation FEWM-2022-0005.

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

 

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For citation:

Sychev A.N. Synthesis of modal and distributed parameters of asymmetric coupled lines with inhomogeneous dielectrics. // Journal of Radio Electronics. – 2024. – ¹. 6. https://doi.org/10.30898/1684-1719.2024.6.7 (In Russian)