Sökning: "lattice based modulation"

Visar resultat 1 - 5 av 12 avhandlingar innehållade orden lattice based modulation.

  1. 1. Multidimensional Modulation Formats for Coherent Single- and Multi-Core Fiber-Optical Communication Systems

    Författare :Tobias Eriksson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; four-dimensional 4D estimates of mutual information MI ; multidimensional modulation formats; lattice based modulation; biorthogonal modulation in eight dimensions; power efficiency; 16-ary quadrature amplitude modulation 16QAM ; quadrature phase shift keying QPSK ; polarization-switched QPSK PS-QPSK ; 128-ary set-partitioning 16QAM 128-SP-16QAM ; spectral efficiency; single parity check-coded modulation; multidimensional position modulation; achievable information rate.; iber-optical communication; multicore fiber transmission; binary pulse position modulation QPSK 2PPM-QPSK ; crosstalk;

    Sammanfattning : This thesis covers multidimensional modulation formats for coherent optical communication systems including spatial division multiplexed systems using multicore fibers. The single-mode optical signal has four dimensions which are spanned by the two orthogonal polarizations and the in-phase and quadrature components. LÄS MER

  3. 2. Multidimensional Constellation Shaping for Coherent Optical Communication Systems

    Författare :Ali Mirani; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lattice-based constellations; geometric shaping; probabilistic shaping; multidimensional modulation format; Voronoi constellation; constellation shaping; optical communications; coherent receiver;

    Sammanfattning : To overcome the increasing demands for Internet traffic, exploiting the available degrees of freedom in optical communication systems is necessary. In this thesis, we study how constellation shaping can be achieved in various dimensions and how various shaping schemes affect the whole performance in real systems. LÄS MER

  4. 3. Signaling for Optical Intensity Channels

    Författare :Johnny Karout; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lattice codes; mutual information; intensity modulation; noncoherent communications; Direct detection; sphere packing.; infrared communications; free-space optical communications; fiber-optical communications;

    Sammanfattning : With the growing popularity of social media services, e-commerce, and many other internet-based services, we are witnessing a rapid growth in the deployment of data centers and cloud computing platforms. As a result, the telecommunications industry has to continue providing additional network capacity to meet the increasing demand for bandwidth. LÄS MER

  5. 4. Efficient 1.3 mm GaInNAs Quantum Well Lasers for Uncooled, High Speed Operation

    Författare :Yongqiang Wei; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; semiconductor laser; uncooled; temperature dependence; modulation; quantum well; molecular beam epitaxy; high speed; GaInNAs;

    Sammanfattning : The rapid expansion of tele and data transmission systems requires an ever increasing capacity in modern optical fibre communication networks. With the implementation of short distance, high density networks, such as access networks, there is a need for cost-effective optical transmitters compatible with single mode fibres. LÄS MER

  7. 5. Theoretical and optical investigations of some III-V based quantum wells and modulation doped heterostructures

    Författare :Thomas Lundström; Maurice S. Skolnick; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis is based on a combination of theoretical calculations and optical studies of the electronic structure and the radiative recombination processes in some III-V based quantum wells and ?-type modulation doped heterostructures. The optical studies includes photoluminescence (PL) spectroscopy, PL excitation (PLE) spectroscopy, and time-resolved PL. LÄS MER