Sökning: "antenna radiation patterns"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden antenna radiation patterns.

1. 1. 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

3. 2. Radiation and Scattering from Conformal Array Antennas

   Författare :Björn Thors; KTH; []
   Nyckelord :conformal antennas; antenna arrays; antenna radiation patterns; radar cross sections; electromagnetic scattering; UTD; moment methods; high frequency method; hybrid method; mutual coupling;

   Sammanfattning : This thesis deals with radiation and scattering fromconformal array antennas. A hybrid technique between the Methodof Moments (MoM) and different asymptotic methods is used forthe analysis, combining the accuracy of the MoM and theefficiency of the asymptotic methods. LÄS MER

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

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

   Sammanfattning : 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. LÄS MER

5. 4. Design and Evaluation of Compact Multi-antennas for Efficient MIMO Communications

   Författare :Ruiyuan Tian; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antenna; propagation channel; MIMO system; wireless communication;

   Sammanfattning : The use of multi-antenna systems with multiple-input multiple-output (MIMO) technology will play a key role in providing high spectrum efficiency for next generation mobile communication systems. This thesis offers valuable insights on the design of compact multi-antennas for efficient MIMO communications. LÄS MER

7. 5. Analysis of Dipole and Patch Antennas in Cylindrical Structures

   Författare :Peter Slättman; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fourier transform; cross-section; patch; slot; arbitrary; EFIE; trough guide; cylindrical; dipole; moment method; antenna; aperture coupled;

   Sammanfattning : This thesis deals with the analysis of dipoles, patches, and aperture coupled patches located in an infinitely long cylindrical structure with arbitrary cross-section. The analysis exploits the two-dimensional nature of the structure by expanding all fields and currents in spatial harmonics along the cylinder axis, and solving the subsequent spectral two-dimensional problems by the moment method. LÄS MER