Sökning: "quadrature amplitude modulation"

Visar resultat 21 - 25 av 26 avhandlingar innehållade orden quadrature amplitude modulation.

  1. 21. Differential Six-port Radio Transceiver for Ultra-wideband and Wideband Antennas

    Författare :Owais Owais; Shaofang Gong; Ke Wu; Linköpings universitet; []
    Nyckelord :;

    Sammanfattning : Requirement for high speed wireless connectivity is propelling research in advanced communication systems. Low power and wide bandwidth of the ultra-wideband technology makes it a potential candidate for high speed data transmission. LÄS MER

  3. 22. Aspects of Power Consumption in Coherent Fiber-Optical Communication Systems

    Författare :Lars Lundberg; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optical frequency comb; Fiber-optical communication; power consumption; carrier-recovery; Raman amplification; energy-efficiency; optical amplifier; digital signal processing; coherent detection; erbium-doped fiber amplifier; phase-tracking;

    Sammanfattning : The power consumption of coherent fiber-optical communication systems is becoming increasingly important, for both environmental and economical reasons. The data traffic on the Internet is increasing at a faster pace than that at which optical network equipment is becoming more energy efficient, which means that the overall power consumption of the Internet is increasing. LÄS MER

  4. 23. On the labeling of Signal Constellations

    Författare :Johan Lassing; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The work in this thesis studies a simple model of a digital communication system in which the transmitter operates on a sequence of information bits by grouping them into blocks of m bits and mapping such blocks onto one out of M = 2m waveforms, which is transmitted over the channel. The receiver recovers the original message by demapping the transmitted signals disturbed by noise back to m-bit blocks using maximum-likelihood symbol detection. LÄS MER

  5. 24. Investigation of Sigma-Delta-over-Fiber for High-Capacity Wireless Communication Systems

    Författare :Husileng Bao; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; millimeter-wave; multipleinput- multiple-output; remote radio head; Radio-over-fiber; central unit;

    Sammanfattning : The advent of beyond-5G (B5G) and 6G technologies brings increases in wireless devices and their applications. Although massive multiple-input-multiple-output (MIMO) delivers high-capacity services using co-located MIMO (CMIMO) technology, distributed MIMO (D-MIMO) technology offers a more uniform user service. LÄS MER

  7. 25. On Performance Analysis of Retransmission Schemes with Fading Channels

    Författare :Peter Larsson; Lars Kildehøj Rasmussen; Mikael Skoglund; Leszek Szczecinsky; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Automatic repeat request; ARQ; hybrid-arq; retransmission schemes; Telecommunication; Telekommunikation;

    Sammanfattning : Future wireless communication systems and services bring increased performance demands, with respect to data-rate(s), reliable communication, (stochastic) real-time guarantees, and more. In this context, not only new communication schemes are needed, but also more capable performance analysis methods are essential. LÄS MER