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Hollow Waveguide (hollow + waveguide)

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Engineering100%

Selected Abstracts

An extended Huygens' principle for modelling scattering from general discontinuities within hollow waveguides

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 5 2001
Ronald L. Ferrari
Abstract The modal fields, generalized scattering matrix (GSM) theory and dyadic Green's functions relating to a general uniform hollow waveguide are briefly reviewed in a mutually consistent normalization. By means of an analysis linking these three concepts, an extended version of the mathematical expression of Huygens' principle is derived, applying to scattering from an arbitrary object within a hollow waveguide. The integral-equation result expresses the total field in terms of the incident waveguide modal fields, the dyadic Green's functions and the tangential electromagnetic field on the surface of the object. It is shown how the extended principle may be applied in turn to perfect conductor, uniform material and inhomogeneous material objects using a quasi method of moments (MM) approach, coupled in the last case with the finite element method. The work reported, which indicates how the GSM of the object may be recovered, is entirely theoretical but displays a close similarity with established MM procedures. Copyright © 2001 John Wiley & Sons, Ltd. [source]

Minimum loss condition of a bent rectangular hollow waveguide

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2009
J. Yamauchi
Abstract The leakage loss of a hollow dielectric waveguide is analyzed analytically and numerically. A minimum loss condition of a bent rectangular hollow waveguide is derived in terms of the refractive index of the cladding using the perturbation method. The validity of the derived minimum loss condition is confirmed by the beam-propagation method. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2901,2902, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24761 [source]

A variational approach to boundary elements,two dimensional Helmholtz problems

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 6 2003
Y. Kagawa
Abstract The boundary element method is a discretized version of the boundary integral equation method. The variational formulation is presented for the boundary element approach to Helmholtz problems. The numerical calculation of the eigenvalues in association with hollow waveguides demonstrates that the variational approach provides the upper and lower bounds of the eigenvalues. The drawback of the discretized system equation must be solved by a trial and error approach, which is shown to be removed by the introduction of the dual reciprocity method. Copyright © 2003 John Wiley & Sons, Ltd. [source]

An extended Huygens' principle for modelling scattering from general discontinuities within hollow waveguides

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 5 2001
Ronald L. Ferrari
Abstract The modal fields, generalized scattering matrix (GSM) theory and dyadic Green's functions relating to a general uniform hollow waveguide are briefly reviewed in a mutually consistent normalization. By means of an analysis linking these three concepts, an extended version of the mathematical expression of Huygens' principle is derived, applying to scattering from an arbitrary object within a hollow waveguide. The integral-equation result expresses the total field in terms of the incident waveguide modal fields, the dyadic Green's functions and the tangential electromagnetic field on the surface of the object. It is shown how the extended principle may be applied in turn to perfect conductor, uniform material and inhomogeneous material objects using a quasi method of moments (MM) approach, coupled in the last case with the finite element method. The work reported, which indicates how the GSM of the object may be recovered, is entirely theoretical but displays a close similarity with established MM procedures. Copyright © 2001 John Wiley & Sons, Ltd. [source]