Search for dissertations about: "Input devices"

Showing result 11 - 15 of 176 swedish dissertations containing the words Input devices.

  1. 11. Microwave Power Devices and Amplifiers for Radars and Communication Systems

    Author : Sher Azam; Qamar ul Wahab; Erik Janzén; Georg Boeck; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Semiconductor physics; Halvledarfysik;

    Abstract : SiC MESFETs and GaN HEMTs posses an enormous potential in power amplifiers at microwave frequencies due to their wide bandgap features of high electric field strength, high electron saturation velocity and high operating temperature. The high power density combined with the comparably high impedance attainable by these devices also offers new possibilities for wideband power microwave systems. READ MORE

  2. 12. Backward and Forward Nonlinear Optical Processes in Potassium Titanyl Phosphate

    Author : Kjell Martin Mølster; Fredrik Laurell; Valdas Pasiskevicius; Ulf L. Österberg; Stefano Taccheo; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; QPM; PPKTP; Nonlinear Optics; Backward second-harmonic; BWOPO; OPO; parametric devices; QPM; Ickelinär Optik; BWOPO; OPO; PPKTP; QPM; kvasifasematching; ikkelinæer optikk; bakovervendt parametrisk oscillator; optisk parametrisk oscillator; PPKTP; Optics and Photonics; Optik och fotonik; Physics; Fysik;

    Abstract : Second-order nonlinear optical processes generate radiation across a broad spectrum, including UV and the far-infrared. In this thesis, new light sources in the near(NIR) and mid infrared (MIR) using three-wave mixing geometries in periodically poled potassium titanyl phosphate (PPKTP) is studied. READ MORE

  3. 13. Novel RF MEMS Devices for W-Band Beam-Steering Front-Ends

    Author : Nutapong Somjit; Joachim Oberhammer; Pierre Blondy; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : This thesis presents novel millimeter-wave microelectromechanical-systems (MEMS) components for W-band reconfigurable beam-steering front-ends. The proposed MEMS components are novel monocrystalline-silicon dielectric-block phase shifters, and substrate-integrated three-dimensional (3D) micromachined helical antennas designed for the nominal frequency of 75 GHz. READ MORE

  4. 14. Design, Fabrication and Characterization of Microwave Passive Devices on Liquid Crystal Polymer Substrates

    Author : Xia Zhang; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; co-planar waveguide; parallel-coupled line resonator; dual-mode ring resonator; millimeter wave; ultra-wideband; Bandpass filter; liquid crystal polymer substrate; printed monopole antenna;

    Abstract : For microwave/millimeter (mm)-wave systems’ applications, as frequency is moving towards higher and higher bands, materials and integration technologies are witnessing higher performance demands and constraints. The materials presently used as mm-wave substrates are either expensive or show unsatisfactory performance. READ MORE

  5. 15. Characterization of Small Antennas & Wireless Devices for MIMO Systems in Multipath & Line-of-Sight

    Author : Ahmed Hussain; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; USRP; OTA; SDR; RIMP; TRP; TIS; Reverberation chamber; Rayleigh; MIMO; LOS; LTE; Throughput;

    Abstract : The current thesis investigates over-the-air (OTA) performance characterization of small antennas and wireless terminals in rich isotropic multipath (RIMP) environment, as well as in pure line-of-sight (LOS) environment when taking into account the random positions and orientations of the mobile terminals caused by the realistic user behavior. The latest mobile wireless terminals such as smart phones and tablets can be used in any random orientation thereby making even a received LOS-component appear as a random voltage at the antenna ports over time. READ MORE