Search for dissertations about: "antenna pattern"

Showing result 1 - 5 of 51 swedish dissertations containing the words antenna pattern.

2. 1. Investigating and Enhancing Performance of Multiple Antenna Systems in Compact MIMO/Diversity Terminals

   Author : Shuai Zhang; Sailing He; Raj Mittra; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multiple antennas; planar inverted-F antenna; mutual coupling; slot antenna; compact antenna; mobile antenna; Q factors; antenna array; ultra-wideband UWB antenna; pattern diversity; polarization diversity; user effects; adaptive arrays; chassis mode;

   Abstract : Today, owners of small communicating device are interested in transmitting or receiving various multimedia data. By increasing the number of antennas at the transmitter and/or the receiver side of the wireless link, the diversity/Multiple-Input Multiple-Output (MIMO) techniques can increase wireless channel capacity without the need for additional power or spectrum in rich scattering environments. READ MORE

4. 2. Embedded Element Patterns in Combination with Circuit Simulations for Multi-Port Antenna Analysis

   Author : Kristian Karlsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antenna efficiency; Greens function; multi-port antenna; impedance matching; reverberation chamber; correlation; antenna arrays; Embedded element pattern; optimization; antenna diversity;

   Abstract : This thesis is a result from work on two different subjects, electromagnetic simulations of reverberation chambers and a methodology for the analysis of multi-port antennas. The subjects can be linked together by their contribution to knowledge in electromagnetic simulations and characterization of antennas. READ MORE

5. 3. Antenna Integrated Superconducting Mixers

   Author : Hans Ekström; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; tapered slotline antenna; mixer; double dipole antenna; superconducting; hot electron; receiver; Niobium; bolometer; trilayer junction; edge junction; Niobium Nitride; SIS;

   Abstract : This thesis investigates the prospects of some different superconducting mixers integrated with planar antennas for the millimeter and submillimeter regime. Two kinds of Superconductor/Insulator/Superconductor (SIS) tunnel junctions for use in mixers have been fabricated; Nb/PbBi edge junctions and Nb trilayer junctions. READ MORE

6. 4. Antenna Limitations and Q-factor Trade-off between Parameters, Steps towards Optimal Antenna Design

   Author : Shuai Shi; Lars Jonsson; Ala Sharaiha; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Antenna limitation; Q-factor; directivity; radiation pattern; current optimization; Electrical Engineering; Elektro- och systemteknik;

   Abstract : Sub-wavelength antennas have become ubiquitous in essential devices, such as mobile phones, sensors, Internet of things (IoT) and machine to machine (M2M) communication devices. Such antennas are often embedded as a small part of the device chassis or their circuit-boards. READ MORE

7. 5. Modeling Approaches for Active Antenna Transmitters

   Author : Parastoo Taghikhani; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thermal model.; MIMO; power amplifier; Active antenna transmitter; hybrid beamforming; electrothermal; active subarray antenna; nonlinear distortion;

   Abstract : The rapid growth of data traffic in mobile communications has attracted interest to Multiple-Input-Multiple-Output (MIMO) communication systems at millimeter-wave (mmWave) frequencies. MIMO systems exploit active antenna arrays transmitter configurations to obtain higher energy efficiency and beamforming flexibility. READ MORE