volume | PIER Journals

2006-11-19

Generalized Equivalent Circuit Model for Transverse Waveguide Slots and Applications

Islam Eshrah,

Prof. Islam Eshrah

Department of Electronics and Communications

Cairo University

Egypt

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Ahmed Kishk,

Professor Ahmed Kishk

Department of Electrical Engineering

University of Mississippi

USA

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Alexander Yakovlev,

Professor Alexander Yakovlev

Department of Electrical Engineering

The University of Mississippi

USA

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Allen Wilburn Glisson

Dr. Allen Wilburn Glisson

Department of Electrical Engineering

The University of Mississippi

USA

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, Vol. 69, 1-20, 2007

doi:10.2528/PIER06110803 | Google Scholar

Abstract

A generalized equivalent circuit model for waveguide transverse slots is proposed for the efficient analysis of waveguide transitions and waveguide slot antennas and slot-excited antennas. The transverse slots on the broad and end waveguide walls analyzed in this paper are decomposed into three structures: two apertures and an auxiliary waveguide section. The slot aperture in the host waveguide is modeled as an inductance-capacitance-transformer (LCT) combination, for which the equivalent inductance and capacitance are determined by first considering the case of zero-thickness slot, then the transformer turns ratio is calculated for the slot on a finite thickness wall. The effect of the wall thickness is accounted for by a waveguide section having cross-sectional dimensions equal to those of the slot, and length equal to the wall thickness. The loaded slot aperture is modeled along with the external load as a lumped load impedance. Expressions for the inductance, capacitance and transformer turns ratio are obtained in terms of the slot length and width. The obtained expressions facilitate the design of a variety of structures, including waveguide couplers, feeding networks and radiators. The equivalent circuit model proved to be accurate compared to the method of moments solution over a wide frequency band. Comparison of the scattering parameters obtained from the circuit analysis, the method of moments, and the finite-difference time-domain solutions exhibit very good agreement.

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Islam Eshrah, Ahmed Kishk, Alexander Yakovlev, and Allen Wilburn Glisson, "Generalized Equivalent Circuit Model for Transverse Waveguide Slots and Applications," , Vol. 69, 1-20, 2007.
doi:10.2528/PIER06110803

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