Sökning: "Propagation Channel"

Visar resultat 21 - 25 av 126 avhandlingar innehållade orden Propagation Channel.

1. 21. 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

3. 22. Fat-IBC : A New Paradigm for Intra-body Communication

   Författare :Noor Badariah Asan; Robin Augustine; Thiemo Voigt; Ali Khaleghi; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fat-Intrabody Communication; Fat Tissue; Microwave; Propagation; Data Packet Reception; Ex-vivo; Phantom; Communication; Reliability; Implants; Engineering Science with specialization in Microwave Technology; Teknisk fysik med inriktning mot mikrovågsteknik;

   Sammanfattning : In the last two decades, a significant development in the field of medical technology occurred worldwide. This development is characterized by the materialization of various body implants and worn devices, that is devices attached to the body. LÄS MER

4. 23. Wireless Sensor Network and Radio Wave Propagation in Harsh Environments

   Författare :Mathias Grudén; Anders Rydberg; Erik Björnemo; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wireless Sensor Network; WISENET; Wave Propagation; Radio Communication; Harsh Environmnents; Engineering Science with specialization in Microwave Technology; Teknisk fysik med inriktning mot mikrovågsteknik;

   Sammanfattning : This licentiate thesis cover two important subjects regarding the application of wireless sensor networks (WSNs). Both subjects are related to propagation mechanisms. The first subject is what the radio channel looks like and how it behaves. LÄS MER

5. 24. Verification of wireless communication performance and robustness for automotive applications

   Författare :Mikael Nilsson; Kommunikationsteknologi; []
   Nyckelord :Vehicle-to-Vehicle; V2V; channel modeling; path loss; two-ray; obstruction; large scale fading; shadow fading; multiple links; diversity; correlation; over-the-air; OTA; multi-probe; multipath propagation simulator; fading emulation;

   Sammanfattning : Today's test methods used for verifying the performance and robustness of automotive applications using wireless communication are often based on fieldtrails, which are time consuming, costly, and not repeatable. Therefore, there is an urgent need for new verification methods that can be performed in lab environment, where the realistic radio propagation environment can be emulated. LÄS MER

7. 25. Multiple-Input Multiple-Output Radio Propagation Channels : Characteristics and Models

   Författare :Kai Yu; Björn Ottersten; David Gesbert; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signalbehandling; Signalbehandling; Signal processing; Signalbehandling;

   Sammanfattning : In recent years, deploying multiple antennas at both transmitter and receiver has appeared as a very promising technology. By exploiting the spatial domain, multiple-input multiple-output (MIMO) systems can support extremely high data rates as long as the environments can provide sufficiently rich scattering. LÄS MER