2025/05/07 by Mustafa Bakr, Bakr, Mustafa, S. Amari +1 · 5 citations
Engineering · Physics and Astronomy · #Advanced Antenna and Metasurface Technologies #Electromagnetic Scattering and Analysis #Electromagnetic Simulation and Numerical Methods #FOS: Physical sciences #Optics (physics.optics)
paper · pdf · doi:10.48550/arxiv.2505.04756
openalex publication_date 2025/05/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The paper presents a detailed study of azimuthally propagating electromagnetic waves in cylindrical metallic cavities with circular cross section. Dispersion characteristics of these waves are determined from Maxwell's equations. Solutions are grouped into branches that account for all known results that are obtained from axial propagation. It is reported that the lowest TE mode starts propagating in the azimuthal direction at a frequency that depends only on the height of the cavity and may be much lower than the cutoff of the TE mode in the axial direction. Universal curves allow the determination of resonant frequencies and field distribution of TE and TM modes in circular cavities containing wedges of arbitrary angles and baffles, with no additional computation. It is shown that the frequency dependence of the propagation constant of a given branch determines all the resonant frequencies of the branch for arbitrary boundary conditions in the azimuthal direction. It is argued that propagation-based models, when applicable, are more accurate than resonance-based models. The lowest TE branch starts at a non-physical resonance. Applications to microwave dual-mode filter design are discussed briefly.