Search for dissertations about: "antennas theory"

Showing result 1 - 5 of 54 swedish dissertations containing the words antennas theory.

2. 1. Decoupling and Evaluation of Multiple Antenna Systems in Compact MIMO Terminals

   Author : Hui Li; Sailing He; Cyril Luxey; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multiple antennas; mutual coupling; compact antennas; frequency reconfigurable antennas; pattern reconfigurable antennas; meta-material antennas; mobile antennas; fractal antennas; collocated antennas; antenna measurement.;

   Abstract : Research on multiple antenna systems has been a hot topic in recent years due to the demands for higher transmission rate and more reliable link in rich scattering environment in wireless communications. Using multiple antennas at both the transmitter side and the receiver side increases the channel capacity without additional frequency spectrum and transmitted power. READ MORE

4. 2. On Reconfigurable MEMS Antennas and Coupling Matrix Estimation

   Author : Marc Mowlér; Björn Lindmark; Björn Ottersten; Pertti Vainikainen; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Telekommunications; Antennas; Estimation Theory; Telecommunication; Telekommunikation;

   Abstract : In this thesis, two different topics are treated related to wireless communication. Part I presents three different reconfigurable MEMS integrated antennas for MIMO applications. Simulation and measurement results are presented along with brief discussions on the topic of antenna selection with reconfigurable antenna elements. READ MORE

5. 3. On signal processing and electromagnetic modelling : applications in antennas and transmission lines

   Author : Jonas Lundbäck; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vector sensors; Statistical signal processing; Antennas; Directional Coupler; Tranmission lines; Partial discharge;

   Abstract : This doctoral thesis is comprised of five parts. The first three parts concern signal processing and electromagnetic modelling of multiport antennas. The last two parts concern signal processing and transmission line theory applied to wave splitting on transmission lines. READ MORE

6. 4. Analysis of Planar and Circular Cylindrical Multilayer Structures with Application to Soft and Hard Surfaces

   Author : Zvonimir Sipus; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antennas; periodic surfaces; integral equations; approximate boundary conditions; soft and hard surfaces; Green s functions; corrugated surfaces; moment method; periodic metal strips; multilayer structures; EFIE; microstrip antennas; spectral domain analysis; group representation theory; strip scatterers;

   Abstract : This thesis deals with the analysis of planar and circular cylindrical multilayer structures, such as strip-loaded dielectric layers, corrugated surfaces and microstrip antennas. In particular, we study corrugations and strip-loaded grounded dielectric slabs when they are used to realize soft and hard surfaces. READ MORE

7. 5. Optimization and Learning for Large-Scale MIMO-OFDM Wireless Systems : Theory, Algorithms, and Applications

   Author : Shashi Kant; Carlo Fischione; Mats Bengtsson; Bo Göransson; Gabor Fodor; Christoph Studer; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; First-Order Optimization; Convex Optimization; ADMM; Three-operator ADMM TOP-ADMM ; EVM; OOBE; PAPR; ACLR; MIMO; OFDM; Federated Learning; Telecommunication; Telekommunikation; Optimeringslära och systemteori; Optimization and Systems Theory; Electrical Engineering; Elektro- och systemteknik;

   Abstract : The requirements for next-generation wireless communications networks, particularly fifth-generation (5G) and beyond, are driven by at least three broad use cases. These include enhanced mobile broadband services to support extremely high data rates in terms of network or per user in both uplink and downlink, massive machine-type communications to accommodate massive internet-of-things applications, and critical machine-type communications to handle mission-critical applications that require ultra-high reliability and low latency. READ MORE