Search for dissertations about: "frequency domain electromagnetics"

Showing result 1 - 5 of 7 swedish dissertations containing the words frequency domain electromagnetics.

  2. 1. Hybrid methods for computational electromagnetics in the frequency domain

    Author : Stefan Hagdahl; KTH; []
    Keywords : Computational Electromagnetics; Hybrid Methods; Boundary Element Method; Geometrical Theory of Diffraction;

    Abstract : In this thesis we study hybrid numerical methods to be usedin computational electromagnetics. We restrict the methods tospectral domain and scattering problems. The hybrids consist ofcombinations of Boundary Element Methods and Geometrical Theoryof Diffraction.In the thesis three hybrid methods will be presented. READ MORE

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

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

    Abstract : 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). READ MORE

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

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

    Abstract : 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. READ MORE

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

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

    Abstract : 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. READ MORE

  7. 5. Implementation of the spectral element method and iterative solution techniques for 3D controlled-source electromagnetic modelling

    Author : Michael Weiss; Thomas Kalscheuer; Michael Becken; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Controlled source electromagnetis; Electromagnetic theory; Numerical modelling; Applied geophysics; Geo-Electromagnetics; Spectral element method; Iterative solution methods; Preconditioning;

    Abstract : Controlled-source electromagnetic methods are imaging techniques applied at/on the surface of the Earth which record the electromagnetic field in order to assess the electrical conductivity distribution of the Earth’s subsurface, along with anomalies in this material property, as well as to characterise and interpret structures in Earth’s crust. Extracting information from the recorded electromagnetic data requires inverse modelling algorithms. READ MORE