Search for dissertations about: "frequency 900 MHz"

Found 4 swedish dissertations containing the words frequency 900 MHz.

  2. 1. Thick Frequency Selective Structures

    Author : Björn Widenberg; Institutionen för elektro- och informationsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustics; Elektromagnetism; optik; akustik; optics; Electromagnetism; Energy Saving Window; Radome; Finite Elemente Method; Frequency Selective Structure; Mode Matching Technique;

    Abstract : This thesis presents a new method that can handle a general thick Frequency Selective Structure (FSS), that consists of an arbitrary number of aperture layers and dielectric layers. The method is based on the Mode Matching Technique (MMT) and the finite element method (FEM). The thesis consists of a General Introduction and five scientific papers. READ MORE

  4. 2. Analysis and Design of Base Station Antennas for Mobile Communications

    Author : Björn Lindmark; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polarization diversity; dual polarization; adaptive antennas; moment method; genetic algorithm; antenna arrays; radio propagation; channel sounding; aperture coupled patch;

    Abstract : The thesis deals with base station antennas and the environment they work in. Polarization diversity, dual band operation, and adaptive antenna systems are discussed with emphasis on how antennas for these applications should be designed. We compare the polarization diversity performance of different types of dual polarized antenna elements. READ MORE

  5. 3. Mass Transport Properties in Supramolecular Systems Studied by Diffusion and Relaxation NMR

    Author : Patrik Jarvoll Dae; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NMR; T2; diffusion; hydrogel; exchange dynamics; T1; magnetic susceptibility; organosilica nanoparticles; microstructure; relaxation; supramolecular systems;

    Abstract : This thesis shows how diffusion and relaxation NMR can be applied in various aspects to study mass transport in supramolecular systems. Information about these systems can be obtained, either by direct measurement of the molecules that are incorporated in a supramolecular structure, or via probe molecules, which indirectly gives information about the system. READ MORE

  6. 4. Acoustic Platform for MXene Synthesis and Electrochemical Behaviour of i-MXenes in Aqueous Electrolytes

    Author : Ahmed El Ghazaly; Johanna Rosén; Ahmed Etman; Husam N. Alshareef; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Surface Acoustic Waves; MXene; i-MXene; Supercapacitor;

    Abstract : Climate Change is believed to be the greatest global challenge and on its forefront is the topic of energy. While being of extreme importance, debates over energy have become a normality. READ MORE