Sökning: "phase-shift"

Visar resultat 11 - 15 av 82 avhandlingar innehållade ordet phase-shift.

  1. 11. Numerical computations of the unsteady flow in a radial turbine

    Författare :Fredrik Hellström; Laszlo Fuchs; Jonas Bredberg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pulsatile flow; radial turbines; pipe flow; effects of inlet conditions; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Non-pulsatile and pulsatile flow in bent pipes and radial turbine has been assessed with numerical simulations. The flow field in a single bent pipe has been computed with different turbulence modelling approaches. LÄS MER

  3. 12. Characterization and Applications of Vector Phase-Sensitive Amplifiers

    Författare :Abel Lorences Riesgo; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; parametric amplification; phase-sensitive amplification; fiber nonlinearities; four-wave mixing; all-optical processing;

    Sammanfattning : This work is devoted to the characterization of vector phase-sensitive amplifiers and processors. A detailed analysis of degenerate vector phase-sensitive amplifier (PSA) is performed.The gain and phase-sensitive extinction ratio are theoretically analyzed using three-wave theory. LÄS MER

  4. 13. Multilevel modulation in short-range optical links

    Författare :Krzysztof Szczerba; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Power and cost efficient short-range optical links are one of the technologies enabling large scale high-performance computers and data centers. Such links typically use directly modulated vertical cavity surface emitting lasers, multi-mode fiber, direct detection and on-off keying (OOK) modulation. LÄS MER

  5. 14. Phase-Sensitive Parametric Signal Processing in Optical Communications

    Författare :Abel Lorences Riesgo; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis covers the analysis of several schemes for parametric processing in fiberoptic communication systems, focusing mainly on phase-sensitive processing. Vector phase-sensitive amplifiers are characterized and phase regeneration of a dualpolarization (DP)-binary phase-shift keying signal (BPSK) signal is experimentally demonstrated. LÄS MER

  7. 15. Phase-Contrast X-Ray Carbon Dioxide Angiography

    Författare :Ulf Lundström; Hans Hertz; Anna Burvall; Ulrich Vogt; Franz Pfeiffer; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Phase-contrast x-ray imaging is an emerging technology, which allows for imaging of smaller features than conventional absorption-based x-ray imaging, with lower radiation dose. Instead of the attenuation that is normally used in x-ray imaging, it utilizes the phase shift introduced by an object to the transmitted x-rays. LÄS MER