Sökning: "polarization diversity"

Visar resultat 1 - 5 av 22 avhandlingar innehållade orden polarization diversity.

1. 1. Space-Time Processing Applications for Wireless Communications

   Författare :Tommy Hult; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Space-Time Processing; Polarization; MIMO; Diversity; HAP;

   Sammanfattning : Wireless mobile communication networks are rapidly growing at an incredible rate around the world and a number of improved and emerging technologies are seen to be critical to the improved economics and performance of these networks. The technical revolution and continuing growth of mobile radio communication systems has been made possible by extraordinary advances in the related fields of digital computing, high-speed circuit technology, the Internet and, of course, digital signal processing. LÄS MER

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

   Författare :Shuai Zhang; Sailing He; Raj Mittra; KTH; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

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

   Författare :Björn Lindmark; Chalmers tekniska högskola; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

5. 4. Investigation of New Concepts and Solutions for Silicon Nanophotonics

   Författare :Zhechao Wang; Lech Wosinski; Kresten Yvind; KTH; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

7. 5. Essays in Political Economy of Development

   Författare :Michele Valsecchi; Göteborgs universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; ethnic diversity; public-private goods; polarization; fractionalization; property rights; land titling; land reform; land inheritance; international migration; political decentralization; political institutions; elections; corruption; natural resource curse; oil; fiscal decentralization; public goods;

   Sammanfattning : Paper 1: Social Conflict, Fractionalization, and Polarization We develop a Conflict model linking Conflict intensity to the distribution of the population over an arbitrary number of groups. We extend the pure contest version of the model by Esteban and Ray (1999: "Conflict and Distribution", Journal of Economic Theory, 87(2): 379-415) to include a mixed public-private good. LÄS MER