Sökning: "Channel measurements"

Visar resultat 16 - 20 av 311 avhandlingar innehållade orden Channel measurements.

  1. 16. Multiantenna Cellular Communications : Channel Estimation, Feedback, and Resource Allocation

    Författare :Emil Björnson; Björn Ottersten; Mats Bengtsson; Marios Kountouris; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; channel estimation; limited feedback; multicell communications; resource allocation;

    Sammanfattning : The use of multiple antennas at base stations and user devices is a key component in the design of cellular communication systems that can meet the capacity demands of tomorrow. The downlink transmission from base stations to users is particularly limiting, both from a theoretical and a practical perspective, since user devices should be simple and power-efficient, and because many applications primarily create downlink traffic (e. LÄS MER

  3. 17. Ultra-Wideband Wireless Channels - Estimation, Modeling and Material Characterization

    Författare :Telmo Santos; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ultra-wideband; channel modeling; channel parameter estimation; material characterization; microwave measurements;

    Sammanfattning : This licentiate thesis is focused on the characterization of ultra-wideband wireless channels. The thesis presents results on ultra-wideband communications as well as on the ultra-wideband characterization of materials. The communications related work consisted in the measurement and modeling of outdoor scenarios envisioned for infostation systems. LÄS MER

  4. 18. Integral Identities for Passive Systems and Spherical Waves in Scattering and Antenna Problems

    Författare :Anders Bernland; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dispersion relations; sum rules; physical limitations; Herglotz functions; electromagnetic scattering; antenna theory; spherical wave expansions; antenna measurements; propagation channel measurements;

    Sammanfattning : Sum rules and physical limitations within electromagnetic theory and antenna theory have received significant attention in the last few years. However, the derivations are often relying on application specific and sometimes unsupported assumptions, and therefore a mathematically rigorous and generally applicable approach seems timely. LÄS MER

  5. 19. Channel Gain Prediction for Cooperative Multi-Agent Systems

    Författare :Markus Fröhle; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Gaussian processes; channel prediction; multi-agent systems; spatial correlation; wireless ad-hoc networks; parameter learning; distributed algorithms;

    Sammanfattning : In a cooperative multi-agent system (MAS), agents communicate with each other using the wireless medium. As agents move in the environment in order to fulfill the MAS' higher level task, their location changes and so does the wireless communication channel they experience. LÄS MER

  7. 20. Channel Prediction and Target Tracking for Multi-Agent Systems

    Författare :Markus Fröhle; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Gaussian processes; multitarget tracking; channel prediction; extended target tracking; Multi-agent system; posterior fusion; location uncertainty;

    Sammanfattning : Mobile moving agents as part of a multi-agent system (MAS) utilize the wireless communication channel to disseminate information and to coordinate between each other. This channel is error-prone and the transmission quality depends on the environment as well as on the configuration of the transmitter and the receiver. LÄS MER