Sökning: "highly nonlinear fiber"

Visar resultat 6 - 10 av 13 avhandlingar innehållade orden highly nonlinear fiber.

  1. 6. Channel-Aware Multilevel Coded Modulation for Coherent Fiber-Optic Communications

    Författare :Lotfollah Beygi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; channel model; multidimensional set partitioning; low-complexity de- tector; coded modulation; signal statistics.; nonlinear phase noise; Fiber-optic communications;

    Sammanfattning : The past decades have shown an ever-increasing demand for high-rate Internet services, motivating a great effort to increase the spectral efficiency of optical networks. In general, fiber-optic links are non-Gaussian, and in contrast to additive white Gaussian noise (AWGN) channels, there is no standard framework for quantifying fundamental limits or designing capacity-approaching coding schemes for such channels. LÄS MER

  2. 7. Tailored fiber lasers and their use in nonlinear optics

    Författare :Peter Zeil; Fredrik Laurell; Andy Clarkson; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

    Sammanfattning : The objective of this thesis work was to develop tailored fiber lasers, which meet the pump requirement for efficient continuous-wave (cw) frequency conversion to the visible and the mid-infrared wavelength regimes: a stable, high-power, wavelength-tunable, narrow-linewidth output in a single polarization. As a first step, the prospect of tuning ytterbium fiber lasers over an unprecedented wavelength range, from 980nm to 1100nm, was investigated. LÄS MER

  3. 8. Advanced nano- and microdomain engineering of Rb-doped KTiOPO4 for nonlinear optical applications

    Författare :Charlotte Liljestrand; Carlota Canalias; Sunao Kurimura; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; KTiOPO4; nonlinear optics; MOPO; quasi-phase matching; SHG; ferroelectrics; domain structuring; periodic poling; Fysik; Physics;

    Sammanfattning : Fine-pitch ferroelectric domain gratings are extensively used for generation of light in the visible and near-infrared spectral regions through quasi-phase matched (QPM) frequency conversion. Sub-μm QPM devices enables demonstration of nonlinear optics with counterpropagating waves, a field of nonlinear optics which remains sparsely explored due to the difficulty of fabricatinghigh quality gratings. LÄS MER

  4. 9. Energy-momentum conserving time-stepping algorithms for nonlinear dynamics of planar and spatial Euler-Bernoulli/Timoshenko beams

    Författare :Sophy Chhang; Jean-Marc Battini; Mohammed Hjiaj; Reijo Kouhia; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nonlinear Dynamics; Energy-momentum conserving scheme; 2D co-rotational beam; Geometrically exact 3D Euler-Bernoulli beam; impact; Byggvetenskap; Civil and Architectural Engineering;

    Sammanfattning : Large deformations of flexible beams can be described using either the co-rotational approach or the total Lagrangian formalism. The co-rotational method is an attractive approach to derive highly nonlinear beam elements because it combines accuracy with numerical efficiency. LÄS MER

  5. 10. 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