Search for dissertations about: "far field"

Showing result 1 - 5 of 553 swedish dissertations containing the words far field.

  2. 1. Optimal Near-field Antenna Apertures in Lossy Media

    Author : Aidin Razavi; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optimal near-field aperture; near-field focusing; near-field antennas; near-field power transfer; array signal processing.; maximum penetration;

    Abstract : Antennas are traditionally designed for far-field applications such as wireless communications, radar, etc., where the antenna systems interact with other systems and objects which are located in the far-field zone of the antennas. READ MORE

  4. 2. Characterization and Design Requirements for Antennas in the Near-field and the Random-LOS Propagation Environment

    Author : Aidin Razavi; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polarization-MIMO; Random-LOS; OTA; Antenna measurements; near-field antennas; antenna characterization; MIMO; near-field focusing;

    Abstract : The choice of antenna for a particular application depends on the requirements imposed by that application. These can be, the application's field region (i.e., near-field or far-field), polarization, radiation pattern, radiation efficiency, system throughput, etc. READ MORE

  5. 3. Strings, Gravitons, and Effective Field Theories

    Author : Igor Buchberger; Marcus Berg; Joseph A. Minahan; Karlstads universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; string theory; amplitudes; supersymmetry; particle phenomenology; BMSSM; modified gravity; bimetric; massive gravity; Lie algebras; ribbon categories; Physics; Fysik;

    Abstract : This thesis concerns a range of aspects of theoretical physics. It is composed of two parts. In the first part we motivate our line of research, and introduce and discuss the relevant concepts. In the second part, four research papers are collected. READ MORE

  6. 4. Effects of impurities on charge transport in graphene field-effect transistors

    Author : Marlene Bonmann; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; carrier transport; electron and hole mobility; impurities; traps; graphene; field-effect transistors; microwave devices; saturation velocity; remote phonons;

    Abstract : In order to push the upper frequency limit of high speed electronics further, thereby extending the range of applications, new device technologies and materials are continuously investigated. The 2D material graphene, with its intrinsically extremely high room temperature charge carrier velocity, is regarded as a promising candidate to push the frequency limit even further. READ MORE

  7. 5. SiC based field effect sensors and sensor systems for combustion control applications

    Author : Mike Andersson; Anita Lloyd Spetz; Udo Weimar; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; SiC; Field Effect Sensors; Combustion Control; Other physics; Övrig fysik;

    Abstract : Increasing oil prices and concerns about global warming have reinforced the interest in biofuels for domestic and district heating, most commonly through combustion of solid biomass like wood logs, hog fuel and pellets. Combustion at non-optimal conditions can, however, lead to substantial emissions of noxious compounds like unburned hydrocarbons, carbon monoxide, and nitrogen oxides as well as the generation of soot. READ MORE