Sökning: "Rayleigh-fading channels"

Visar resultat 26 - 30 av 40 avhandlingar innehållade orden Rayleigh-fading channels.

  1. 26. Signal Processing Aspects of Massive MIMO and IRS-Aided Communications

    Författare :Özgecan Özdogan; Emil Björnson; Erik G. Larsson; Mari Kobayashi; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The data traffic in cellular networks has grown at an exponential pace for decades. This trend will most probably continue in the future, driven by new innovative applications. One of the key enablers of future cellular networks is the massive MIMO technology, and it has been started to be commercially deployed in many countries. LÄS MER

  3. 27. On Bit-interleaved Coded Modulation with QAM Constellations

    Författare :Alex Alvarado; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Bit-interleaved coded modulation (BICM) is a flexible modulation/coding scheme which allows the designer to choose a modulation constellation independently of the coding rate. This is because the output of the channel encoder and the input to the modulator are separated by a bit-level interleaver. LÄS MER

  4. 28. HARQ Systems: Resource Allocation, Feedback Error Protection, and Bits-to-Symbol Mappings

    Författare :Chaitanya Tumula V. K.; Erik G. Larsson; Danyo Danev; Ana I. Pérez-Neira; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HARQ Systems; Resource Allocation; Geometric Programming; 3GPP-LTE; PUCCH Format 2; Complex-field coding; Signal Space Diversity; Optimization; Superposition Coding;

    Sammanfattning : Reliability of data transmission is a fundamental problem in wireless communications. Fading in wireless channels causes the signal strength to vary at the receiver and this results in loss of data packets. To improve the reliability, automatic repeat request (ARQ) schemes were introduced. LÄS MER

  5. 29. Adaptive Modulation and Coding in Wireless Communications with Feedback

    Författare :Sorour Falahati; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : We study link adaptation techniques which are suitable for the future packet-based wireless communication systems, where in particular, flat Rayleigh fading channels are assumed. Firstly, an adaptive coding scheme based on Rate Compatible Convolutional (RCC) codes is proposed. LÄS MER

  7. 30. On the Performance of Underlay Cognitive Radio Networks with Interference Constraints and Relaying

    Författare :Charles Kabiri; Blekinge Tekniska Högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cognitive Radio Networks; Cognitive Cooperative Relay Networks; Underlay Spectrum Access; Interference Constraint; Outage Constraint;

    Sammanfattning : Efficiently allocating the scarce and expensive radio resources is a key challenge for advanced radio communication systems. To this end, cognitive radio (CR) has emerged as a promising solution which can offer considerable improvements in spectrum utilization. LÄS MER