Sökning: "Electromagnetic scattering"

Visar resultat 1 - 5 av 70 avhandlingar innehållade orden Electromagnetic scattering.

  1. 1. Design and Characterization of Functional Structures for Electromagnetic Waves

    Detta är en avhandling från Department of Electrical and Information Technology, Lund University

    Författare :Andreas Ericsson; Lunds universitet.; Lund University.; [2017-10-03]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electromagnetic scattering; functional structure; circular polarization selective structure; reflector antenna; electromagnetic absorber; radar cross section; compressive sensing; triaxial weave; homogenization; physical optics;

    Sammanfattning : This dissertation deals with design and characterization of functional structures for scattering of electromagnetic waves. An abundance of these structures can be found in nature, such as the structural coloration in the feathers of a peacock, the scales of butterflies and the shell of scarab beetles. LÄS MER

  2. 2. Shape Optimization for Electromagnetic and Quasimagnetostatic Applications

    Detta är en avhandling från Department of Electrical and Information Technology, Lund University

    Författare :Per Jacobsson; [2006]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; shape optimization; continuum sensitivity; electromagnetic scattering; adjoint problem;

    Sammanfattning : This thesis uses a continuum formulation of sensitivity for shape optimization in two-dimensional microwave scattering and quasimagnetostatic problems. The continuum sensitivity is obtained by solving an appropriate adjoint problem. LÄS MER

  3. 3. Radiation and Scattering from Conformal Array Antennas

    Detta är en avhandling från Stockholm : Alfvénlaboratoriet

    Författare :Björn Thors; KTH.; [2003]
    Nyckelord :conformal antennas; antenna arrays; antenna radiation patterns; radar cross sections; electromagnetic scattering; UTD; moment methods; high frequency method; hybrid method; mutual coupling;

    Sammanfattning : This thesis deals with radiation and scattering fromconformal array antennas. A hybrid technique between the Methodof Moments (MoM) and different asymptotic methods is used forthe analysis, combining the accuracy of the MoM and theefficiency of the asymptotic methods. LÄS MER

  4. 4. Accurate techniques for 2D electromagnetic scattering

    Detta är en avhandling från Växjö : Linnaeus University

    Författare :Imad Akeab; Linnéuniversitetet.; [2014]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Integral equations; method of moments; sparsity; scaling; shadow boundary; B-S;

    Sammanfattning : This thesis consists of three parts. The first part is an introduction and referencessome recent work on 2D electromagnetic scattering problems at high frequencies. It alsopresents the basic integral equation types for impenetrable objects. A brief discussionof the standard elements of the method of moments is followed by summaries of thepapers. LÄS MER

  5. 5. Interaction between Electromagnetic Waves and Localized Plasma Oscillations

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Jan-Ove Hall; Uppsala universitet.; [2004]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; space physics; plasma physics; radio waves; ionospheric modification; density depleations; field-aligned irregularities; lower hybrid solitary structures; lower hybrid cavities; Z mode waves; magnetosonic waves; scattering; mode conversion; Rymd- och plasmafysik; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Space physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Rymdfysik;

    Sammanfattning : This thesis treats interaction between electromagnetic waves and localized plasma oscillations. Two specific physical systems are considered, namely artificially excited magnetic field-aligned irregularities (striations) and naturally excited lower hybrid solitary structures (LHSS). LÄS MER