Penetration Through Slots in Overmoded Cavities

Campione, Salvatore; Warne, Larry

doi:10.1109/temc.2021.3067005

Title: Penetration Through Slots in Overmoded Cavities

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Abstract

A resonant cavity undergoes three distinct behaviors with increasing frequency: 1) fundamental modes, localized in frequency with well defined modal distribution; 2) undermoded region, where modes are still separated, but are sufficiently perturbed by small imperfections that their spectral positions (and distributions) are statistical in nature; and 3) overmoded region, where modes overlap, field distributions follow stochastic distributions, and the slot acts as if in free space. Understanding the penetration through slots in the overmoded region is of great interest, and is the focus of this article. Since full-wave solvers may not be able to provide a timely answer for very high frequencies due to a lack of memory and/or computation resources, we develop bounding methods to estimate worst-case average and maximum fields within the cavity. Finally, after discussing the bounding formulation, we compare its results to full-wave simulations at the first, second, and third resonance supported by the slot in the case of a cylindrical cavity. Note that the bounding formulation indicates that results are nearly independent of cavity shape: only the cavity volume, frequency, and cavity quality factor affect the overmoded region, making this formulation a powerful tool to assess electromagnetic interference and electromagnetic compatibility effects within cavities.

Authors:

Campione, Salvatore ^[1]; Warne, Larry ^[1]

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Publication Date:: Thu Apr 22 00:00:00 EDT 2021

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA); USDOE Laboratory Directed Research and Development (LDRD) Program

OSTI Identifier:: 1781557

Report Number(s):: SAND-2021-3695J
Journal ID: ISSN 0018-9375; 695207

Grant/Contract Number:: AC04-94AL85000; NA0003525

Resource Type:: Accepted Manuscript

Journal Name:: IEEE Transactions on Electromagnetic Compatibility

Additional Journal Information:: Journal Volume: 63; Journal Issue: 6; Journal ID: ISSN 0018-9375

Publisher:: IEEE

Country of Publication:: United States

Language:: English

Subject:: shielding effectiveness; power balance; overmoded cavity; slots; quality factor

Citation Formats


                    Campione, Salvatore, and Warne, Larry. Penetration Through Slots in Overmoded Cavities.  United States: N. p., 2021. 
Web.  doi:10.1109/temc.2021.3067005.

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                    Campione, Salvatore, & Warne, Larry. Penetration Through Slots in Overmoded Cavities.  United States.  https://doi.org/10.1109/temc.2021.3067005

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                    Campione, Salvatore, and Warne, Larry. Thu .  
"Penetration Through Slots in Overmoded Cavities".  United States.  https://doi.org/10.1109/temc.2021.3067005.  https://www.osti.gov/servlets/purl/1781557.

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@article{osti_1781557,

  title        = {Penetration Through Slots in Overmoded Cavities},

  author       = {Campione, Salvatore and Warne, Larry},

  abstractNote = {A resonant cavity undergoes three distinct behaviors with increasing frequency: 1) fundamental modes, localized in frequency with well defined modal distribution; 2) undermoded region, where modes are still separated, but are sufficiently perturbed by small imperfections that their spectral positions (and distributions) are statistical in nature; and 3) overmoded region, where modes overlap, field distributions follow stochastic distributions, and the slot acts as if in free space. Understanding the penetration through slots in the overmoded region is of great interest, and is the focus of this article. Since full-wave solvers may not be able to provide a timely answer for very high frequencies due to a lack of memory and/or computation resources, we develop bounding methods to estimate worst-case average and maximum fields within the cavity. Finally, after discussing the bounding formulation, we compare its results to full-wave simulations at the first, second, and third resonance supported by the slot in the case of a cylindrical cavity. Note that the bounding formulation indicates that results are nearly independent of cavity shape: only the cavity volume, frequency, and cavity quality factor affect the overmoded region, making this formulation a powerful tool to assess electromagnetic interference and electromagnetic compatibility effects within cavities.},

  doi          = {10.1109/temc.2021.3067005},

  journal      = {IEEE Transactions on Electromagnetic Compatibility},

  number       = 6,

  volume       = 63,

  place        = {United States},

  year         = {Thu Apr 22 00:00:00 EDT 2021},

  month        = {Thu Apr 22 00:00:00 EDT 2021}

}

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