The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Ismo V. Lindell - One of the best experts on this subject based on the ideXlab platform.
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Electromagnetic Source Decomposition for Generalized Decomposable Bi-Anisotropic Media
Journal of Electromagnetic Waves and Applications, 2012Co-Authors: L.h. Puska, Ismo V. LindellAbstract:The classical TE/TM decomposition theory, valid for isotropic and uniaxially Anisotropic Media, has recently been generalized to a class of bi-Anisotropic Media. In such a decomposable medium any electromagnetic field can be decomposed into two individual electromagnetic fields, an a-field and a b-field, satisfying certain polarization conditions. The natural continuation of the theory is to decompose the electromagnetic sources that is the topic of the present paper. The differential equations for the a- and b-sources are derived and seen to generalize the previous results. Also one example of possible source decomposition is suggested.
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Potentials in Bi-Anisotropic Media
Journal of Electromagnetic Waves and Applications, 2001Co-Authors: Ismo V. Lindell, Frank OlyslagerAbstract:Potential representations for electromagnetic fields are considered for linear bi-Anisotropic Media. Representations in terms of two vector potentials are possible for any bi-Anisotropic Media. However, representations in terms of two scalar potentials are associated with Media in which fields can be decomposed in two partial fields with special polarization restrictions. This kind of Media have been studied before and they define the class of decomposable bi-Anisotropic Media. Potential representations in terms of two scalar potentials are derived for fields in decomposable bi-Anisotropic Media in two different ways and the results are shown to coincide. The expressions obtained give the previously known potential representations in isotropic and decomposable Anisotropic Media as special cases.
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Potential representation of electromagnetic fields in decomposable Anisotropic Media
Journal of Physics D: Applied Physics, 2000Co-Authors: Ismo V. LindellAbstract:An electromagnetic field representation in terms of two scalar potential functions, generalized Hertz potentials, is introduced to fields outside the source region in a certain class of Anisotropic Media. The class is labelled decomposable Anisotropic Media, a generalization of uniaxial Anisotropic Media, in which any electromagnetic fields outside the sources can be decomposed into TE and TM partial fields with respect to two axial directions defined by the medium. A potential representation is introduced by first expressing the fields in terms of their axial components. Instead of differential equations of the fourth order, satisfied by the field vectors, the potential functions are shown to satisfy second-order differential equations which reduce to the classical ones for the special cases of isotropic and uniaxially Anisotropic Media. A comparison of solving the electromagnetic field vectors through potentials or axial field components is briefly discussed.
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Electromagnetic Source Decomposition for Generalized Decomposable Bi-Anisotropic Media
Journal of Electromagnetic Waves and Applications, 1999Co-Authors: L.h. Puska, Ismo V. LindellAbstract:The classical TE/TM decomposition theory, valid for isotropic and uniaxially Anisotropic Media, has recently been generalized to a class of bi-Anisotropic Media. In such a decomposable medium any electromagnetic field can be decomposed into two individual electromagnetic fields, an a-field and a b-field, satisfying certain polarization conditions. The natural continuation of the theory is to decompose the electromagnetic sources that is the topic of the present paper. The differential equations for the a- and b-sources are derived and seen to generalize the previous results. Also one example of possible source decomposition is suggested.
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Generalized decomposition of electromagnetic fields in bi-Anisotropic Media
IEEE Transactions on Antennas and Propagation, 1998Co-Authors: Ismo V. Lindell, Frank OlyslagerAbstract:TE/TM decomposition of electromagnetic fields, with respect to one special direction in space, is well known to be valid for fields in isotropic and uniaxially Anisotropic Media. The theory was recently generalized to bi-Anisotropic Media by defining the decomposition for linear combinations of electric and magnetic fields with respect to two vectors. In the present paper, the theory is further generalized by defining the decomposition with respect to four vectors (two six-vectors), which restrict the polarizations of the decomposed electromagnetic fields. It is shown that the class of bi-Anisotropic Media in which electromagnetic fields can be decomposed into two independent electromagnetic fields (a-field and b-field) is more general than in all previous decomposition theories. It is also shown that the decomposed a- and b-fields see the original bi-Anisotropic medium as simpler equivalent ones (aand b-Media) for which analytic Green dyadics were previously derived by these authors.
C H Chapman - One of the best experts on this subject based on the ideXlab platform.
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reflection transmission coefficient reciprocities in Anisotropic Media
Geophysical Journal International, 1994Co-Authors: C H ChapmanAbstract:SUMMARY Reciprocal relationships between the plane-wave reflection/transmission coefficients in Anisotropic Media are derived directly from the transformed wave equations without use of Betti’s theorem. If the eigensolutions are normalized correctly, coefficients with the r8les of the incident and generated waves reversed are equal, provided the sign of slowness parallel to the interface is also reversed.
Jessé C. Costa - One of the best experts on this subject based on the ideXlab platform.
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Vertical image waves in elliptically Anisotropic Media
Studia Geophysica et Geodaetica, 2008Co-Authors: Jörg Schleicher, Amélia Novais, Jessé C. CostaAbstract:By reparameterization of the kinematic expressions for remigration in elliptically Anisotropic Media using a new ellipticity parameter, we derive a new image-wave equation in elliptically Anisotropic Media describing the position of the reflector as a function of the medium ellipticity. This image wave equation, which is a kind of medium-dependent one-way wave equation, can be used for automatically stretching a time-migrated image in depth until wells are tied or other given geologic criteria are met. In this way, it provides a useful means to use a priori depth information for finding an estimate of the vertical velocity, which cannot be detected from time processing only. Simple numerical examples confirm the validity of the image-wave equation even for nonconstant velocity.
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Vertical Image Waves in Elliptically Anisotropic Media
69th EAGE Conference and Exhibition incorporating SPE EUROPEC 2007, 2007Co-Authors: Jörg Schleicher, Amélia Novais, Jessé C. CostaAbstract:P284 Vertical Image Waves in Elliptically Anisotropic Media J. Schleicher* (Campinas State University (Unicamp)) A. Novais (Unicamp) & J.C. Costa (UFPa) SUMMARY By reparameterization of the kinematic expressions for remigration in elliptically Anisotropic Media using a new ellipticity parameter we derive a new image wave equation in elliptically Anisotropic Media describing the position of the reflector as a function of the medium ellipticity. This image wave equation which is a kind of medium-dependent one-way wave equation can be used for automatically stretching a time-migrated image in depth until wells are tied or other given geologic criteria are met. In this
Vladimir K. Ignatovich - One of the best experts on this subject based on the ideXlab platform.
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Optics of Anisotropic Media
Physics-Uspekhi, 2012Co-Authors: Filipp V. Ignatovich, Vladimir K. IgnatovichAbstract:A new effective analytical approach to describing electromagnetic waves in nonmagnetic Anisotropic Media is proposed. An analytical description of the refraction and reflection at an interface between isotropic and Anisotropic Media is demonstrated. Beam splitting upon reflection and refraction is reviewed, and surface wave generation is examined. D'yakonov surface waves and methods of their observation are discussed. Analytical and numerical calculations of the reflection and transmission of plane-parallel uniaxial plates are outlined.
Frank Olyslager - One of the best experts on this subject based on the ideXlab platform.
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Potentials in Bi-Anisotropic Media
Journal of Electromagnetic Waves and Applications, 2001Co-Authors: Ismo V. Lindell, Frank OlyslagerAbstract:Potential representations for electromagnetic fields are considered for linear bi-Anisotropic Media. Representations in terms of two vector potentials are possible for any bi-Anisotropic Media. However, representations in terms of two scalar potentials are associated with Media in which fields can be decomposed in two partial fields with special polarization restrictions. This kind of Media have been studied before and they define the class of decomposable bi-Anisotropic Media. Potential representations in terms of two scalar potentials are derived for fields in decomposable bi-Anisotropic Media in two different ways and the results are shown to coincide. The expressions obtained give the previously known potential representations in isotropic and decomposable Anisotropic Media as special cases.
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Generalized decomposition of electromagnetic fields in bi-Anisotropic Media
IEEE Transactions on Antennas and Propagation, 1998Co-Authors: Ismo V. Lindell, Frank OlyslagerAbstract:TE/TM decomposition of electromagnetic fields, with respect to one special direction in space, is well known to be valid for fields in isotropic and uniaxially Anisotropic Media. The theory was recently generalized to bi-Anisotropic Media by defining the decomposition for linear combinations of electric and magnetic fields with respect to two vectors. In the present paper, the theory is further generalized by defining the decomposition with respect to four vectors (two six-vectors), which restrict the polarizations of the decomposed electromagnetic fields. It is shown that the class of bi-Anisotropic Media in which electromagnetic fields can be decomposed into two independent electromagnetic fields (a-field and b-field) is more general than in all previous decomposition theories. It is also shown that the decomposed a- and b-fields see the original bi-Anisotropic medium as simpler equivalent ones (aand b-Media) for which analytic Green dyadics were previously derived by these authors.