Sökning: "CHANNEL"

Visar resultat 1 - 5 av 1743 avhandlingar innehållade ordet CHANNEL.

  1. 1. Channel Estimation and Prediction for 5G Applications

    Författare :Rikke Apelfröjd; Mikael Sternad; Emil Björnson; Uppsala universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Channel estimation; Channel prediction; Channel smoothing; Linear estimation; Kalman filter; Massive MIMO; Coordinated Multipoint transmission; Robust precoding; Predictor antennas; Limits of predictability; Long range predictions; Electrical Engineering with specialization in Signal Processing; Elektroteknik med inriktning mot signalbehandling;

    Sammanfattning : Accurate channel state information (CSI) is important for many candidate techniques of future wireless communication systems. However, acquiring CSI can sometimes be difficult, especially if the user equipment is mobile in which case the future channel realisations must be estimated/predicted. LÄS MER

  2. 2. 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

  3. 3. Channel Related Optimization of Wireless Communication Systems

    Författare :Fredrik Tufvesson; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; time division duplex; multicarrier; Radio communication; orthogonal frequency division multiplex; channel estimation; pilot symbol assisted modulation; sub-channel spacing; sub-channel bandwidth; interchannel interference; cyclic prefix; intersymbol interference; Rayleigh fading; precoding; pre-compensation;

    Sammanfattning : This thesis deals with different optimization problems in the design of wireless communication systems. It is mainly directed to the design of systems based on multicarrier techniques and orthogonal frequency division multiplex, OFDM, but some of the problems apply to single carrier systems as well. LÄS MER

  4. 4. Prediction of Mobile Radio Channels : Modeling and Design

    Författare :Torbjörn Ekman; Rodney Vaughan; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Systemteknik; mobile radio channel; fading; channel model; channel estimation; channel prediction; power prediction; Systemteknik; Systems engineering; Systemteknik; Signal Processing; signalbehandling;

    Sammanfattning : Prediction of the rapidly fading envelope of a mobile radio channel enables a number of capacity improving techniques like fast resource allocation and fast link adaptation. This thesis deals with linear prediction of the complex impulse response of a channel and unbiased quadratic prediction of the power. LÄS MER

  5. 5. Source-Channel Coding in Networks

    Författare :Niklas Wernersson; Mikael Skoglund; Geoffrey Chan; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; source coding; channel coding; joint source-channel coding; bandwidth expansion; distributed source coding; multiple description coding; soft decoding; Telecommunication; Telekommunikation;

    Sammanfattning : The aim of source coding is to represent information as accurately as possible using as few bits as possible and in order to do so redundancy from the source needs to be removed. The aim of channel coding is in some sense the contrary, namely to introduce redundancy that can be exploited to protect the information when being transmitted over a nonideal channel. LÄS MER