Penetration through Slots in Cylindrical Cavities Operating at Fundamental Cavity Modes in the Presence of Electromagnetic Absorbers

doi:https://doi.org/10.2528/pierm20060803

Title: Penetration through Slots in Cylindrical Cavities Operating at Fundamental Cavity Modes in the Presence of Electromagnetic Absorbers

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Abstract

Placing microwave absorbing materials into a high-quality factor resonant cavity may in general reduce the large interior electromagnetic fields excited under external illumination. In this study, we aim to combine two analytical models we previously developed: 1) an unmatched formulation for frequencies below the slot resonance to model shielding effectiveness versus frequency; and 2) a perturbation model approach to estimate the quality factor of cavities in the presence of absorbers. The resulting model realizes a toolkit with which design guidelines of the absorber's properties and location can be optimized over a frequency band. Analytic predictions of shielding effectiveness for three transverse magnetic modes for various locations of the absorber placed on the inside cavity wall show good agreement with both full-wave simulations and experiments, and validate the proposed model. This analysis opens new avenues for specialized ways to mitigate harmful fields within cavities.

Authors:

Campione, Salvatore ^[1]; Warne, Larry Kevin ^[1]; Reines, Isak C. ^[1]; Gutierrez, Roy K. ^[1]; Williams, Jeffery T. ^[1]

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

Publication Date:: 2020-01-01

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:: 1667389

Report Number(s):: SAND-2020-8542J
Journal ID: ISSN 1937-8726; 690015

Grant/Contract Number:: AC04-94AL85000; NA-0003525

Resource Type:: Journal Article: Accepted Manuscript

Journal Name:: Progress in Electromagnetics Research M

Additional Journal Information:: Journal Volume: 96; Journal ID: ISSN 1937-8726

Publisher:: EMW Publishing

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; cavity; slots; electromagnetic absorber; quality factor; shielding effectiveness; unmatched formulation; perturbation model

Citation Formats


                    Campione, Salvatore, Warne, Larry Kevin, Reines, Isak C., Gutierrez, Roy K., and Williams, Jeffery T. Penetration through Slots in Cylindrical Cavities Operating at Fundamental Cavity Modes in the Presence of Electromagnetic Absorbers.  United States: N. p., 2020. 
        Web.  doi:10.2528/pierm20060803.

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                    Campione, Salvatore, Warne, Larry Kevin, Reines, Isak C., Gutierrez, Roy K., & Williams, Jeffery T. Penetration through Slots in Cylindrical Cavities Operating at Fundamental Cavity Modes in the Presence of Electromagnetic Absorbers.  United States.  https://doi.org/10.2528/pierm20060803

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                    Campione, Salvatore, Warne, Larry Kevin, Reines, Isak C., Gutierrez, Roy K., and Williams, Jeffery T. Wed .  
        "Penetration through Slots in Cylindrical Cavities Operating at Fundamental Cavity Modes in the Presence of Electromagnetic Absorbers".  United States.  https://doi.org/10.2528/pierm20060803.  https://www.osti.gov/servlets/purl/1667389.

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@article{osti_1667389,

  title        = {Penetration through Slots in Cylindrical Cavities Operating at Fundamental Cavity Modes in the Presence of Electromagnetic Absorbers},

  author       = {Campione, Salvatore and Warne, Larry Kevin and Reines, Isak C. and Gutierrez, Roy K. and Williams, Jeffery T.},

  abstractNote = {Placing microwave absorbing materials into a high-quality factor resonant cavity may in general reduce the large interior electromagnetic fields excited under external illumination. In this study, we aim to combine two analytical models we previously developed: 1) an unmatched formulation for frequencies below the slot resonance to model shielding effectiveness versus frequency; and 2) a perturbation model approach to estimate the quality factor of cavities in the presence of absorbers. The resulting model realizes a toolkit with which design guidelines of the absorber's properties and location can be optimized over a frequency band. Analytic predictions of shielding effectiveness for three transverse magnetic modes for various locations of the absorber placed on the inside cavity wall show good agreement with both full-wave simulations and experiments, and validate the proposed model. This analysis opens new avenues for specialized ways to mitigate harmful fields within cavities.},

  doi          = {10.2528/pierm20060803},

  url          = {https://www.osti.gov/biblio/1667389},
  journal      = {Progress in Electromagnetics Research M},

  issn         = {1937-8726},

  number       = ,

  volume       = 96,

  place        = {United States},

  year         = {2020},

  month        = {1}

}

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