Download or read book Scattering of electromagnetic waves by two and three dimensional dielectric bodies written by Halûk Uygur Tosun and published by . This book was released on 1976 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scattering of Electromagnetic Waves by Buried Dielectric Bodies written by K. K. Mei and published by . This book was released on 1977 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent development in the unimoment method has brought finite difference and finite element methods into the computational techniques of electromagnetic scattering. In this paper the various finite methods and their potentials in the scattering computations are examined. A section on programming technique is included for those uninitiated and the applications of the finite methods in 2-dimensional and 3-dimensional scattering problems, together with some of the associated computational subject matters are presented. (Author).

Download or read book Interaction of Electromagnetic Waves with Biological Tissue written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The interaction of electromagnetic waves with biological tissue is investigated. Two problems in particular are studied. The first is three-dimensional scattering from biological tissue taking into consideration its dispersive nature. The other problem that is investigated is the thre -dimensional reconstruction of the dielectric properties of a body from the scattered field data resulting from interrogation with electromagnetic waves. The symmetric condensed node transmission line matrix method (SCN TLM) is used to study three-dimensional scattering from biological tissue. To simulate the dispersive nature of biological tissue, a second order Debye equation approximation of the permittivity in the frequency domain is used in a modified TLM technique. In this technique, the scattering matrix is independent of the dielectric properties of the medium, which are accounted for via lumped equivalent networks or sources connected to the nodes. These equivalent sources are calculated at each time step and includedin the scattering procedure of the TLM. To check the validity and accuracy of the modified TLM technique for dispersive homogeneous and nonhomogeneous dielectric bodies, some of the results of the numerical simulations are compared to those obtained analytically. Assuming a nondispersive nature of biological tissue, the nondispersive or stub-loaded SCN TLM method is used to obtain the near field data and hence the specific absorption rate (SAR) distribution. The results of both cases are compared. The modified TLM technique is then applied to a nonhomogeneous and geometrically complex dispersive dielectric body, which is the human head. To estimate the complex permittivities of three-dimensional inhomogeneous dielectric bodies, the unrelated illumination method is used. This method, which has been tested before with two-dimensional bodies, is extended to handle three-dimensional inhomogeneous dielectric bodies. The method utilizes the method of moments (MoM) to di.

Download or read book Three dimensional Electromagnetic Scattering from a Circular Tube of Finite Length written by Cheng C. Kao and published by . This book was released on 1970 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scattering Two Volume Set written by E. R. Pike and published by Elsevier. This book was released on 2001-10-09 with total page 1831 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scattering is the collision of two objects that results in a change of trajectory and energy. For example, in particle physics, such as electrons, photons, or neutrons are "scattered off" of a target specimen, resulting in a different energy and direction. In the field of electromagnetism, scattering is the random diffusion of electromagnetic radiation from air masses is an aid in the long-range sending of radio signals over geographic obstacles such as mountains. This type of scattering, applied to the field of acoustics, is the spreading of sound in many directions due to irregularities in the transmission medium. Volume I of Scattering will be devoted to basic theoretical ideas, approximation methods, numerical techniques and mathematical modeling. Volume II will be concerned with basic experimental techniques, technological practices, and comparisons with relevant theoretical work including seismology, medical applications, meteorological phenomena and astronomy. This reference will be used by researchers and graduate students in physics, applied physics, biophysics, chemical physics, medical physics, acoustics, geosciences, optics, mathematics, and engineering. This is the first encyclopedic-range work on the topic of scattering theory in quantum mechanics, elastodynamics, acoustics, and electromagnetics. It serves as a comprehensive interdisciplinary presentation of scattering and inverse scattering theory and applications in a wide range of scientific fields, with an emphasis, and details, up-to-date developments. Scattering also places an emphasis on the problems that are still in active current research. The first interdisciplinary reference source on scattering to gather all world expertise in this technique Covers the major aspects of scattering in a common language, helping to widening the knowledge of researchers across disciplines The list of editors, associate editors and contributors reads like an international Who's Who in the interdisciplinary field of scattering

Download or read book Electromagnetic And Acoustic Scattering Detection And Inverse Problems Proceedings Of The Conference written by Claude Bourrely and published by World Scientific. This book was released on 1989-03-01 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contents:Light Scattering Problems in Astrophysics (J M Perrin)Surface Integral Operators and their Use in Acoustics and Electromagnetics (A Berthon)Acoustic Diffraction by Slender Bodies of Arbitrary Shape (M Tran-Van-Nhieu)High and Low Energy Approximations for the Electromagnetic Scattering by Irregular Objects (B Torresani)Electromagnetic Scattering and Mutual Interactions Between Closely Spaced Spheroids (J Dalmas & R Deleuil)Acoustical Imaging of 2D Fluid Targets Buried in a Half Space: A Diffraction Tomography Approach Using Line-Sources Insonification (B Duchene et al)Contribution of Radar Polarimetry in Radar Target Discrimination. The “Poincaré Planisphere”: a New Representation Method (E Pottier)Electromagnetic and Acoustic Waves in Random Media: from Propagation to Anderson Localization (B Souillard)Weak Disorder: Homogeneisation Method and Propagation (C Bardos)Coherent Propagation of Surface Acoustic Waves in Quasi-Periodic and Random Arrays of Grooves (D Sornette et al)On Asymptotic Behaviour of Waves States in Random Media (F Bentosela & R Rodriguez)A Study of Acoustic Transmission of Transient Signal in a Inhomogeneous Medium with the Help of a Wavelet Transform. Application to an Air-Water Plane Interface (G Saracco & Ph Tchamitchian)Three-Dimensional Impedance Scattering Theory (P Sabatier)Survey of Optimization Algorithms Applied to Inverse Problems (A Roger)A Linearized Inverse Problem: Acoustic Impedance Tomography of Biological Media (J P Lefebvre)and others Readership: Electrical engineers and mathematicians.

Download or read book The Fast Multipole Method for Electromagnetic Wave Scattering from Three dimensional Dielectric Objects written by George Papadopoulos and published by . This book was released on 1998 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interaction of Electromagnetic Waves with Biological Tissue written by Inas El Babli and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interaction of electromagnetic waves with biological tissue is investigated. Two problems in particular are studied. The first is three-dimensional scattering from biological tissue taking into consideration its dispersive nature. The other problem that is investigated is the thre -dimensional reconstruction of the dielectric properties of a body from the scattered field data resulting from interrogation with electromagnetic waves. The symmetric condensed node transmission line matrix method (SCN TLM) is used to study three-dimensional scattering from biological tissue. To simulate the dispersive nature of biological tissue, a second order Debye equation approximation of the permittivity in the frequency domain is used in a modified TLM technique. In this technique, the scattering matrix is independent of the dielectric properties of the medium, which are accounted for via lumped equivalent networks or sources connected to the nodes. These equivalent sources are calculated at each time step and includedin the scattering procedure of the TLM. To check the validity and accuracy of the modified TLM technique for dispersive homogeneous and nonhomogeneous dielectric bodies, some of the results of the numerical simulations are compared to those obtained analytically. Assuming a nondispersive nature of biological tissue, the nondispersive or stub-loaded SCN TLM method is used to obtain the near field data and hence the specific absorption rate (SAR) distribution. The results of both cases are compared. The modified TLM technique is then applied to a nonhomogeneous and geometrically complex dispersive dielectric body, which is the human head. To estimate the complex permittivities of three-dimensional inhomogeneous dielectric bodies, the unrelated illumination method is used. This method, which has been tested before with two-dimensional bodies, is extended to handle three-dimensional inhomogeneous dielectric bodies. The method utilizes the method of moments (MoM) to discretize the nonlinear integral equation, which relates the scattered field data and the complex permittivity. Yet, it differs from the other reconstruction techniques in that the way of acquiring information helps overcoming the ill-posedness nature of the problem. This is maintained by the proper arrangement of the polarization and the direction of the incident electric fields aiming to illuminate the body with a group of unrelated incident fields. Numerical simulations are carried out to assess the method and to test its robustness in the presence of measured data uncertainties.

Download or read book Generalized Multipole Techniques for Electromagnetic and Light Scattering written by T. Wriedt and published by Elsevier. This book was released on 1999-12-01 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an edited volume of nine papers covering the different variants of the generalized multipole techniques (GMT). The papers were presented at the recent 3rd Workshop on Electromagnetics and Light Scattering - Theory and Applications, which focused on current GMT methods. These include the multiple multipole method (MMP), the discrete sources method (DSM), Yasuura's method, method of auxiliary sources and null-field method with discrete sources. Each paper presents a full theoretical description as well as some applications of the method in electrical engineering and optics. It also includes both 2D and 3D methods and other applications developed in the former Soviet Union and Japan.

Download or read book Scattering of Electromagnetic Waves by Buried Or Partly Buried Inhomogeneous Bodies of Revolution written by Henry Shing-Horng Chang and published by . This book was released on 1980 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electromagnetic Wave Propagation Radiation and Scattering written by Akira Ishimaru and published by John Wiley & Sons. This book was released on 2017-10-27 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the most methodical treatments of electromagnetic wave propagation, radiation, and scattering—including new applications and ideas Presented in two parts, this book takes an analytical approach on the subject and emphasizes new ideas and applications used today. Part one covers fundamentals of electromagnetic wave propagation, radiation, and scattering. It provides ample end-of-chapter problems and offers a 90-page solution manual to help readers check and comprehend their work. The second part of the book explores up-to-date applications of electromagnetic waves—including radiometry, geophysical remote sensing and imaging, and biomedical and signal processing applications. Written by a world renowned authority in the field of electromagnetic research, this new edition of Electromagnetic Wave Propagation, Radiation, and Scattering: From Fundamentals to Applications presents detailed applications with useful appendices, including mathematical formulas, Airy function, Abel’s equation, Hilbert transform, and Riemann surfaces. The book also features newly revised material that focuses on the following topics: Statistical wave theories—which have been extensively applied to topics such as geophysical remote sensing, bio-electromagnetics, bio-optics, and bio-ultrasound imaging Integration of several distinct yet related disciplines, such as statistical wave theories, communications, signal processing, and time reversal imaging New phenomena of multiple scattering, such as coherent scattering and memory effects Multiphysics applications that combine theories for different physical phenomena, such as seismic coda waves, stochastic wave theory, heat diffusion, and temperature rise in biological and other media Metamaterials and solitons in optical fibers, nonlinear phenomena, and porous media Primarily a textbook for graduate courses in electrical engineering, Electromagnetic Wave Propagation, Radiation, and Scattering is also ideal for graduate students in bioengineering, geophysics, ocean engineering, and geophysical remote sensing. The book is also a useful reference for engineers and scientists working in fields such as geophysical remote sensing, bio–medical engineering in optics and ultrasound, and new materials and integration with signal processing.

Download or read book From Analytic to Numerical Electromagnetics Contributions by C Yeh and his collaborators written by C.Yeh and published by Dog Ear Publishing. This book was released on 2018-03-20 with total page 850 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on properly organized reprints by C. Yeh and his collaborators, innovative and original solutions to a number of fundamental problems, essential to the teaching and research in modern electromagnetics, are presented in From Analytic to Numerical Electromagnetics. The wide range of coverage from general applied theory to the pioneering development of canonical solutions and numerical methods offers a rare in-depth understanding of the methods used in solving complex problems in classical and modern electromagnetics. Selected specific examples of solved problems are: New derivation of boundary conditions, conditions for scalar wave approximation, completeness of the far-zone data, correct power loss calculation, limitations of directional coupler theory, calculation of noise temperature of lossy plate, canonical solutions for elliptic, parabolic or spheroidal dielectric structures, waves in periodic medium, focused beam scattering, relativistically moving medium, terahertz low-loss waveguides, WDM optical fiber solitons, particle radiation in complex medium, and being the first to develop these numerical methods - FEM, BPM, 4x4 Matrix Method, EBCM, TLM, and 2 Point Boundary Method - to solve complex Electromagnetics problems. Readers will find the subjects covered in this book to be a useful supplement to a standard advanced textbook on electromagnetics. To researchers and engineers, From Analytic to Numerical Electromagnetics will be a valuable reference and guide to obtain solutions to problems dealing with optical communications, optical solitons, photonics, and terahertz, plasmonic, metamaterial or nano waveguides.

Download or read book Fast Higher Order Solutions for Electromagnetic Scattering From Three Dimensional Bodies written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mathematical Modeling in Diffraction Theory written by Alexander G. Kyurkchan and published by Elsevier. This book was released on 2015-09-19 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mathematical Modeling in Diffraction Theory: Based on A Priori Information on the Analytical Properties of the Solution provides the fundamental physical concepts behind the theory of wave diffraction and scattered wave fields as well as its application in radio physics, acoustics, optics, radio astronomy, biophysics, geophysics, and astrophysics. This book provides a coherent discussion of several advanced topics that have the potential to push forward progress in this field. It begins with examples illustrating the importance of taking a priori information into account when developing algorithms for solving diffraction problems, with subsequent chapters discussing the basic analytical representations of wave fields, the auxiliary current and source methods for solving the problems of diffraction at compact scatterers, the null field and matrix methods that are widely used to solve problems in radio-physics, radio-astronomy, and biophysics, and the continued boundary condition and pattern equation method. Provides ideas and techniques for obtaining a priori information on analytical properties of wave fields and provides methods for solving diffraction problems Includes numerous concrete examples of localization of singularities of analytical continuation of wave fields Presents a qualitative explanation of the formation of visions of objects Formulates the concept of “invisible objects Supplies appropriate computer programs for all presented methods

Download or read book Electromagnetic Scattering by a Three dimensional Object Composed of an Orthorhombic Dielectric Magnetic Medium Endowed with Magnetoelectric Gyrotropy written by Hamad Alkhoori and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The main purpose of this research is to investigate scattering of an electromagnetic field by a three-dimensional nonspherical object (e.g, spheroid, ellipsoid, etc.) composed of an orthorhombic dielectric-magnetic medium endowed with magnetoelectric gyrotropy. The relative permittivity dyadic must be a scalar multiple of the relative permeability dyadic, and the constitutive principal axes can be arbitrarily oriented with respect to the shape principal axes.Scattering by nonspherical objects fits many realistic situations. Furthermore, the interplay of shape anisotropy and medium anisotropy as well as their simultaneous effect on scattering may provide useful features that are not exhibited by objects composed of isotropic mediums. Possible examples include low scattering and high absorption, which can be useful in designing structures for stealth applications. I used the extended boundary condition method (EBCM) to study electromagnetic scattering by a three-dimensional object composed of the chosen medium. Known vector spherical wave functions were used to represent the fields in the surrounding matter-free space. After I derived closed-form expressions of the vector spherical wave functions for the chosen medium (available in coordinate-free form but not in closed-form), the internal fields were represented as superpositions of those vector spherical wave functions. Application of the EwaldOseen extinction theorem and the Huygens principle then yielded a transition matrix to relate the unknown scattered field coefficients to the known incident field coefficients.Numerical results were obtained for scattering of a plane wave by an ellipsoid composed of the chosen medium. The scattering, absorption, and extinction efficiencies were calculated thereby in relation to: (i) the shape of the object, (ii) the constitutive-anisotropy parameters of the permittivity and permeability dyadics, (iii) the magnetoelectric-gyrotropy vector, and (iv) the orientation of the constitutive principal axes with respect to the shape principal axes.A study on the shape of the object and the constitutive-anisotropy parameters revealed that the total scattering efficiency can be smaller than the absorption efficiency for some configurations of the incident plane wave but not necessarily for others. The shape of the object has a stronger influence on the total scattering efficiency than on the absorption efficiency. Even though the ellipsoid is not necessarily a body of revolution, it is anisotropic, and it is not impedance matched to free space, the backscattering efficiency can be minuscule but the forward-scattering efficiency is not.The effects of the magnetoelectric-gyrotropy vector can be envisioned in that both the total scattering and forward-scattering efficiencies are maximum when the plane wave is incident in a direction coparallel (but not antiparallel) to the magnetoelectric-gyrotropy vector, and the backscattering efficiency is minimum when the magnetoelectric-gyrotropy vector is parallel to the incidence direction. The total scattering and forward-scattering efficiencies are maximum when the incidence direction is parallel to the largest semi-axis of the ellipsoid if the incidence direction is coparallel (but not antiparallel) to the magnetoelectric-gyrotropy vector. From these results, I concluded that Lorentz nonreciprocity in an object is intimately connected to the shape of that object in affecting the scattered field.The orientation of the constitutive principal axes with respect to the shape principal axes has a noticeable effect on the total scattering and absorption efficiencies as the electrical size increases. Furthermore, the polarization state of the incident plane wave has a more visible effect on the total scattering and absorption efficiencies for ellipsoids compared to spheres. As an application that involves the chosen medium of this research, I determined sufficient conditions for zero backscattering from an object composed of the chosen medium and suspended in an isotropic dielectric-magnetic medium endowed with magnetoelectric gyrotropy by an analysis of the transition matrix. The elements of the transition matrix must satisfy certain conditions for zero backscattering. Numerical results obtainedthereby showed that the sufficient set of three zero-backscattering conditions are as follows: (i) The object is a body of revolution with the incident plane wave propagating along the axis of revolution. (ii) The impedances of both mediums are equal. (iii) The magnetoelectric-gyrotropy vectors of both mediums are aligned along the axis of revolution, whether or not both magnetoelectric-gyrotropy vectors are co-parallel.

Download or read book A Study of the Analysis and Measurements of Three dimensional Arbitrarily shaped Dielectric Scatterers written by Johnson Jenn-Hwa Wang and published by . This book was released on 1980 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this program is to conduct theoretical and experimental research to determine the electromagnetic scattering from heterogeneous dielectric bodies as individual bodies and as a cluster of bodies. The discrepancies in the literature regarding the singularity of the electric dyadic Green's functions were resolved and a unified and consistent view is presented. Compact range scattering measurements at 1 GHz were successfully performed to obtain measured data to validate the numerical analyses. Extensive computations were made for a variety of dielectric scatterers, including a one-foot bird at 1 GHz. The agreements between measurement and computation were good except for the resonant sphere, for which the calculated resonant frequencies were shifted by about 20 percent. Various numerical techniques were investigated successfully for implementation in the volume methods to treat symmetrical scatterers through use of symmetric matrices, the use of banded matrices, and virtual memory. A new local-file manipulation technique for handling large matrices has been explored and found to be potentially useful. There has been very little research into the problem of scattering by dielectric objects of complex permittivity. Future research in this area should include the investigation of the surface integral equation technique and the exact solution for the dielectric prolate spheroid. (Author).

Download or read book Two Dimensional Electromagnetic Scattering from a Dielectric Coated Conductor written by Clayton V. Stewart and published by . This book was released on 1975 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thesis deals with electromagnetic scattering from a dielectric coated, conducting cylinder of arbitrary cross section and of infinite length. The incident field is assumed to be a uniform plane wave traveling normal to the axis of the scatterer. The integral equations for the transverse electric case are derived and discretized for numerical solution. The Hadamard principle value is used to handle high order singularities in the integral equations. A computer program RAMCS has been developed to solve for the two dimensional radar cross section for the case of a lossless dielectric coating. The numerical solution is formulated in terms of the method of moments. Results are presented for circular cylindrical scattering bodies.