Sökning: "Propagation environments"

Visar resultat 1 - 5 av 79 avhandlingar innehållade orden Propagation environments.

1. 1. Propagation environment modeling using scattered field chamber

   Författare :Magnus Otterskog; Dag Stranneby; Pertti Vainikainen; Örebro universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reverberation Chamber; Scattered Field Chamber; Propagation environments; Antenna measurements; Electrical engineering; Elektroteknik; Elektronik; Electronics;

   Sammanfattning : This thesis covers the development of the Reverberation Chamber as a measurement tool for cell phone tests in electronic production. It also covers the development of the Scattered Field Chamber as a measurement tool for simulations of real propagation environments. LÄS MER

3. 2. Acoustic Sound Source Localisation and Tracking : in Indoor Environments

   Författare :Anders Johansson; Blekinge Tekniska Högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Room acoustics; Speaker localisation; Tracking; State-space filter; Sequential Monte Carlo method; Particle filter;

   Sammanfattning : With advances in micro-electronic complexity and fabrication, sophisticated algorithms for source localisation and tracking can now be deployed in cost sensitive appliances for both consumer and commercial markets. As a result, such algorithms are becoming ubiquitous elements of contemporary communication, robotics and surveillance systems. LÄS MER

4. 3. 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. 4. Multiple Antenna Terminals in Realistic Environments - A Composite Channel Modeling Approach

   Författare :Fredrik Harrysson; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Channel model; MIMO; multiple antennas terminal; propagation; user interaction; vehicular channel; diversity; spatial multiplexing; channel measurement;

   Sammanfattning : For evaluation of specific antenna arrangements in wireless communication systems we need physical channel models that take into account also the directional domain of the propagation channel. In this thesis we investigate, validate and propose a practical approach to wireless channel modeling and, particularly, to mobile communication systems. LÄS MER

7. 5. Doctoral Thesis: Massive MIMO in Real Propagation Environments

   Författare :Xiang Gao; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Massive MIMO; very-large MIMO; multi-user MIMO; channel measurements; channel modeling; 5G; sum-rate capacity; antenna selection; signal processing;

   Sammanfattning : Mobile communications are now evolving towards the fifth generation (5G). In the near future, we expect an explosive increase in the number of connected devices, such as phones, tablets, sensors, connected vehicles and so on. Much higher data rates than in today's 4G systems are required. LÄS MER