Sökning: "Orthogonal frequency division multiplexing"

Visar resultat 1 - 5 av 45 avhandlingar innehållade orden Orthogonal frequency division multiplexing.

  1. 1. Diversity and Interference Aspects in the Downlink of Code Division Multiple Access Systems

    Författare :Anders Persson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; orthogonal frequency division multiplexing; multi-carrier modulation; Rayleigh-fading channels; code division multiple access; frequency-selective channels; multiple access interference; diversity;

    Sammanfattning : This thesis consists of six included papers and technical reports, plus an introduction. The topic studied is interference and diversity aspects in code division multiple access (CDMA) systems for mobile cellular communications. The focus in the papers is on the downlink - the communication link from the base station to the mobile terminal. LÄS MER

  3. 2. Single frequency broadcasting networks

    Författare :Göran Malmgren; KTH; []
    Nyckelord :;

    Sammanfattning : An Orthogonal Frequency Division Multiplexing (OFDM) schemeallows all transmitters in a radio network to transmitidentical signals in the same frequency block, forming a socalled Single Frequency Network (SFN). By avoiding frequencyreuse, substantial improvements in bandwidth utilisation arepossible. LÄS MER

  4. 3. Pulse Shape Adaptation and Channel Estimation in Generalised Frequency Division Multiplexing Systems

    Författare :Jinfeng Du; Svante Signell; Ben Slimane; Arne Svenssons; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; OFDM; GFDM; OQAM; pulse shaping; adaptation; channel estimation; Electronics; Elektronik;

    Sammanfattning : Orthogonal Frequency Division Multiplexing (OFDM) is well known as an efficient technology for wireless communications and is widely used in many of the current and upcoming wireless and wireline communication standards. However, it has some intrinsic drawbacks, e.g. LÄS MER

  5. 4. Massive Multi-Antenna Communications with Low-Resolution Data Converters

    Författare :Sven Jacobsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; orthogonal frequency-division multiplexing; channel estimation; quantization; linear precoding; convex optimization; nonlinear precoding; linear combing; hardware impairments; analog-to-digital converter; beamforming; Massive multi-user multiple-input multiple-output; digital-to-analog converter;

    Sammanfattning : Massive multi-user (MU) multiple-input multiple-output (MIMO) will be a core technology in future cellular communication systems. In massive MU-MIMO systems, the number of antennas at the base station (BS) is scaled up by several orders of magnitude compared to traditional multi-antenna systems with the goals of enabling large gains in capacity and energy efficiency. LÄS MER

  7. 5. Contributions to Frequency Offset and Time Delay Estimation

    Författare :Mattias Olsson; Håkan Johansson; Jonny Holmberg; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; time delay estimation; OFDM; carrier frequency offset; Signal processing; Signalbehandling;

    Sammanfattning : The demand for reliable high rate and efficient communication is ever increasing. In this thesis we look at two different problems in such systems, and their possible solutions. LÄS MER