Sökning: "B. Lars G. Jonsson"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden B. Lars G. Jonsson.

  1. 1. Efficient Methods to Calculate Mutual Coupling between Generic Antennas on Large Platforms

    Författare :Johan Malmström; B. Lars G. Jonsson; Lars Pettersson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis presents research on methods for calculating the mutual coupling between antennas. The mutual coupling between antennas is a measure of the amount of energy transmitted from one antenna that is received by another, and is a key parameter when installing antennas on platforms, such as aircraft. LÄS MER

  3. 2. Directional Decomposition in Anisotropic Heterogeneous Media for Acoustic and Electromagnetic Fields

    Författare :B. Lars G. Jonsson; KTH; []
    Nyckelord :directional wave-field decomposition; wave splitting; spectral reduction; aourstic anisotropy; electromagnetic anisotropy; generalized eigenvalue problem;

    Sammanfattning : Directional wave-field decomposition for heterogeneousanisotropic media with in-stantaneous response is establishedfor both the acoustic and the electromagnetic equations.We derive a sufficient condition for ellipticity of thesystem's matrix in the Laplace domain and show that theconstruction of the splitting matrix via a Dunford-Taylorintegral over the resolvent of the non-compact, non-normalsystem's matrix is well de ned. LÄS MER

  4. 3. Fundamental Bounds on Performance of Periodic Electromagnetic Radiators and Scatterers

    Författare :Andrei Ludvig-Osipov; B. Lars G. Jonsson; Christophe Caloz; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Q-factor; bandwidth; antenna arrays; periodic structures; physical bounds; physical limitations; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : In this thesis, the optimal bandwidth performance of periodic electromagnetic radiators and scatterers is studied. The main focus is on the development and application of methods to obtain fundamental physical bounds, relating geometrical parameters, frequency bandwidth, efficiency and radiation characteristics of periodic electromagnetic structures. LÄS MER

  5. 4. Analysis and Optimization of Installed Antenna Performance

    Författare :Henrik Frid; B. Lars G. Jonsson; Hugh Griffiths; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : This Ph.D. thesis consists of six papers, which are labeled with roman numerals. Papers I-III have already been presented in a licentiate thesis published in2017, and this Ph. LÄS MER

  7. 5. Ab initio modelling of interfaces in nanocomposites for high voltage insulation

    Författare :Elena Kubyshkina; B. Lars G. Jonsson; Mikael Unge; Per-Olof Åstrand; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Dielectric nanocomposite materials have been experimentally proven to have properties that are beneficial in applications for efficient energy transport. However, today there are still no empirical models or rules that can predict the performance of a certain combination of materials in the nanocomposite, and there are also no definitive explanations of their dielectric behavior. LÄS MER