Sökning: "nonlinear device modelling"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden nonlinear device modelling.

  1. 1. Nonlinear Characterisation and Modelling of Microwave Semiconductor Devices

    Författare :Mattias Thorsell; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; noise modelling; nonlinear measurement; active load-pull; noise measurement; thermal characterisation; AlGaN GaN HEMT; nonlinear modelling;

    Sammanfattning : There is an increasing need for more accurate models taking into account the nonlinearities and memory effects of microwave transistors. The memory effects are especially important for transistor technologies suffering from relatively large low frequency dispersion, such as GaN baed HEMTs. LÄS MER

  3. 2. Characterisation and Modelling of Graphene FETs for Terahertz Mixers and Detectors

    Författare :MICHAEL ANDERSSON; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; graphene; millimetre and submillimetre waves; power detectors; nonlinear device modelling; microwave amplifiers; nanofabrication; integrated circuits; noise modelling; Field-effect transistors FETs ; terahertz detectors; Volterra; subharmonic resistive mixers;

    Sammanfattning : Graphene is a two-dimensional sheet of carbon atoms with numerous envisaged applications owing to its exciting properties. In particular, ultrahigh-speed graphene field effect transistors (GFETs) are possible due to the unprecedented carrier velocities in ideal graphene. LÄS MER

  4. 3. Modelling and experimental testing of truck tyre rolling resistance

    Författare :Jukka Hyttinen; Lars Drugge; Jenny Jerrelind; James Busfield; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Truck tyre; PRF; filler-reinforced rubber; ambient temperature; rubber testing; constitutive modelling; parametrisation; rolling resistance; load cell; Fletcher-Gent effect; Payne effect; Lastbilsdäck; PRF; förstärkande fyllmedel; gummi; omgivningstemperatur; gummiprovning; konstitutiv modellering; parametrisering; rullmotstånd; lastcell; Fletcher-Gent effekt; Payne effekt; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : Truck transport offers a versatile way to ship goods in regional, long haulage and urban applications. However, the heavy truck sector accounts for 6 % of total greenhouse gas emissions in the European Union. Therefore, there is a need for a substantial reduction of these emissions to secure the sustainability of Earth for future generations. LÄS MER

  5. 4. Microwave Frequency Stability and Spin Wave Mode Structure in Nano-Contact Spin Torque Oscillators

    Författare :Anders Eklund; B. Gunnar Malm; Johan Åkerman; Mikael Östling; Erik Wahlström; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spintronics; microwave oscillators; magnetization dynamics; spin waves; phase noise; device modelling; electrical characterization; X-ray microscopy; STXM; XMCD; Fysik; Physics; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : The nano-contact spin torque oscillator (NC-STO) is an emerging device for highly tunable microwave frequency generation in the range from 0.1 GHz to above 65 GHz with an on-chip footprint on the scale of a few μm. LÄS MER

  7. 5. Optical Parametric Devices in Periodically Poled LiTaO3

    Författare :Martin Levenius; Katia Gallo; Valdas Pasiskevicius; Giuseppe Leo; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nonlinear optics; parametric processes; frequency downconver-sion; quasi-phase matching; LiTaO3; broadband downconversion; quadratic cascading; nonlinear photonic crystals; twin-beam generation;

    Sammanfattning : Optical parametric frequency conversion based on quasi phase matching (QPM) in nonlinear optical crystals is a powerful technique for generating coherent radiation in wavelength ranges spanning from the mid-infrared (mid-IR) to the blue, displaying low thermal load and high efficiency.This thesis shows how QPM in one- (1D) or two-dimensional (2D) lattices can be employed to engineer novel devices for parametric downconversion in the IR, af-fording freedom in designing both spectral and angular properties of the parametric output. LÄS MER