Sökning: "Channel measurements"

Visar resultat 11 - 15 av 311 avhandlingar innehållade orden Channel measurements.

  1. 11. Measurement-Based Modeling of Wireless Propagation Channels - MIMO and UWB

    Författare :Johan Kåredal; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; personal area networks; MIMO; channel modeling; Propagation; channel measurements; vehicle-to-vehicle communicationa; ultra-wideband;

    Sammanfattning : Future wireless systems envision higher speeds and more reliable services but at the same time face challenges in terms of bandwidth being a limited resource. Two promising techniques that can provide an increased throughput without requiring additional bandwidth allocation are multiple-input multiple-output (MIMO) systems and ultra-wideband (UWB) systems. LÄS MER

  3. 12. 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

  4. 13. 60 GHz Wireless Propagation Channels: Characterization, Modeling and Evaluation

    Författare :Carl Gustafson; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 60 GHz; mm-wave; IEEE 802.11ad; IEEE802.15.3c; Channel measurements; Channel modeling; propagation; MIMO; Beamforming; Spatial Multiplexing;

    Sammanfattning : To be able to connect wirelessly to the internet is nowadays a part of everyday life and the number of wireless devices accessing wireless networks worldwide are increasing rapidly. However, with the increasing number of wireless devices and applications and the amount available bandwidth, spectrum shortage is an issue. LÄS MER

  5. 14. Predictor Antennas : Enabling channel prediction for fast-moving vehicles in wireless broadband systems

    Författare :Joachim Björsell; Mikael Sternad; Anders Ahlén; Fredrik Tufvesson; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Predictor antenna; Channel prediction; Long-range prediction; Massive MIMO; Spline interpolation; Channel aging; Outdated CSI; Electrical Engineering with specialization in Signal Processing; Elektroteknik med inriktning mot signalbehandling;

    Sammanfattning : Many advanced transmission techniques utilize channel state information (CSI) at the transmitter (CSIT) to improve throughput, spectral efficiency, power efficiency, and other performance metrics. Estimating CSI accurately is important to fully benefit from many of these techniques. LÄS MER

  7. 15. Modeling of Multiple-Input Multiple-Output Radio Propagation Channels

    Författare :Kai Yu; KTH; []
    Nyckelord :Antenna Array; Wireless Communications; MIMO Channel Model; MIMO Channel Measurements; MIMO Channel Capacity;

    Sammanfattning : In recent years, multiple-input multiple-output (MIMO)systems appear to be very promising since they can provide highdata rates in environments with sucient scattering byexploiting the spatial domain. To design a real MIMO wirelesssystem and predict its performance under certain circumstances,it is necessary to have accurate MIMO wireless channel modelsfor dierent scenarios. LÄS MER