Search for dissertations about: "finite-difference time-domain method"

Showing result 16 - 20 of 48 swedish dissertations containing the words finite-difference time-domain method.

  2. 16. Computation of EMC Properties of Slots and Printed Circuit Boards

    Author : Jan Carlsson; RISE; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; corrugations; crosstalk; FDTD; spectral domain; EFIE; chokes; Finite Difference Method; printed circuit board; transmission line network; EMC analysis; PCB; transmission line theory; radiated emission; Method of moments; MM; MoM; electric field integral equation; soft and hard surfaces; slot; radiated susceptibility;

    Abstract : This thesis deals with the numerical solution of electromagnetic compatibility (EMC) problems for electronic systems, such as radiated emission, susceptibility and crosstalk on printed circuit boards and transmission through slots. The analysis of printed circuit boards is done by using an electric field integral equation (EFIE) expressed in the frequency domain, which is solved by using the method of moments. READ MORE

  4. 17. Topology optimization of antennas and waveguide transitions

    Author : Emadeldeen Hassan; Martin Berggren; Daniel Noreland; Eddie Wadbro; Mats Gustafsson; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Maxwell s equations; topology optimization; antennas; waveguide transition; finite-difference time-domain; gradient-based optimization; adjoint-field problem; microwave devices.; business data processing; administrativ databehandling;

    Abstract : This thesis introduces a topology optimization approach to design, from scratch, efficient microwave devices, such as antennas and waveguide transitions. The design of these devices is formulated as a general optimization problem that aims to build the whole layout of the device in order to extremize a chosen objective function. READ MORE

  5. 18. High order summation-by-parts methods in time and space

    Author : Tomas Lundquist; Jan Nordström; Peter Eliasson; David A. Kopriva; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; summation-by-parts; time integration; stiff problems; weak initial conditions; high order methods; simultaneous-approximation-term; finite difference; discontinuous Galerkin; spectral methods; conservation; energy stability; complex geometries; non-conforming grid interfaces; interpolation;

    Abstract : This thesis develops the methodology for solving initial boundary value problems with the use of summation-by-parts discretizations. The combination of high orders of accuracy and a systematic approach to construct provably stable boundary and interface procedures makes this methodology especially suitable for scientific computations with high demands on efficiency and robustness. READ MORE

  6. 19. Investigation of New Concepts and Solutions for Silicon Nanophotonics

    Author : Zhechao Wang; Lech Wosinski; Kresten Yvind; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Planar integrated circuit; silicon photonics; slot waveguide; finite-difference time-domain; waveguide grating coupler; ring resonator; polarization diversity scheme; polarization beam splitter; polarization rotator; hybrid silicon laser; epitaxial lateral overgrowth; chemical-mechanical polishing.; Optics; Optik;

    Abstract : Nowadays, silicon photonics is a widely studied research topic. Its high-index-contrast and compatibility with the complementary metal-oxide-semiconductor technology make it a promising platform for low cost high density integration. READ MORE

  7. 20. Stable FEM-FDTD Hybrid Method for Maxwell's Equations

    Author : Thomas Rylander; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Finite Element Method; scattering; antennas; stability analysis; edge elements; Maxwell s equations; NASA almond; microwave circuits; mass lumping; proof of stability; explicit-implicit time-stepping; Finite-Differences Time-Domain;

    Abstract : In this thesis edge elements are applied to solve several problems in computational electromagnetics. In particular, a hybrid scheme joining the Finite Element Method (FEM) and the Finite-Difference Time-Domain (FDTD) algorithm is developed, tested and exploited. READ MORE