Sökning: "computational electromagnetics"

Visar resultat 1 - 5 av 26 avhandlingar innehållade orden computational electromagnetics.

  1. 1. Computational electromagnetics : software development and high frequency modeling of surface currents on perfect conductors

    Författare :Sandy Sefi; Jesper Oppelstrup; Francisco Saez de Adana; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; High frequency approximations; Maxwell’s equations; Method of Moments; Physical Optics; Geometrical Theory of Diffraction; Extraction Extrapolation; Numerical analysis; Numerisk analys;

    Sammanfattning : In high frequency computational electromagnetics, rigorous numerical methods be come unrealistic tools due to computational demand increasing with the frequency. Instead approximations to the solutions of the Maxwell equations can be employed to evaluate th electromagnetic fields. LÄS MER

  3. 2. Inverse and optimization problems in electromagnetics -- a finite-element method perspective

    Författare :JOHAN WINGES; Chalmers tekniska högskola; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microwave measurements; computational electromagnetics; finite element method; optimization; inductive power transfer; compressed sensing; wireless power; brick-tetrahedron hybrid; parameter estimation; inverse problems;

    Sammanfattning : In this thesis, a selection of inverse and optimization problems are studied where the finite element method (FEM) serves as a comprehensive tool to solve electromagnetic field problems that lack an analytic solution. The inverse problems are typically formulated in terms of an optimization problem where the misfit between a measurement and the corresponding result of a computational model is minimized. LÄS MER

  4. 3. Hybrid Methods for Computational Electromagnetics in Frequency Domain

    Författare :Stefan Hagdahl; Björn Engquist; Lars Pettersson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Maxwell s equations; Geometrical Theory of Diffraction; Smooth Surface Diffraction; Boundary Element Method; Hybrid methods; Electromagnetic Scattering; Numerical analysis; Numerisk analys;

    Sammanfattning : In this thesis we study hybrid numerical methods to be used in computational electromagnetics. The purpose is to address a wide frequency range relative to a given geometry. We also focus on efficient and robust numerical algorithms for computing the so called Smooth Surface Diffraction predicted by Geometrical Theory of Diffraction (GTD). LÄS MER

  5. 4. Material distribution-based topology optimization for wave propagation problems

    Författare :Ahmad Hasnain Bokhari; Eddie Wadbro; Martin Berggren; Roland Herzog; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; topology optimization; material distribution; wave propagation problems; Helmholtz equation; acoustics; electromagnetics; plasmonics;

    Sammanfattning : This thesis employs material distribution-based topology optimization for wave propagation problems. In the material distribution approach, we define a material indicator function that models the presence and absence of material in a design domain. LÄS MER

  7. 5. Simulation of Electro-Optic Modulators by a Time-Domain Beam-Propagation Method

    Författare :Elin Solberg; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; time-domain beam-propagation method; finite element method; tensor products; computational electromagnetics; photonics; electro-optic modulators; finite element method;

    Sammanfattning : Electro-optic modulators (EOMs) are components which convert electric signals to optical ones. They are needed, e.g., at the transmitter end of fiber-optic communication systems and in time-stretch analog-to-digital converters. LÄS MER