Sökning: "wide band"

Visar resultat 1 - 5 av 233 avhandlingar innehållade orden wide band.

  1. 1. Wide-angle scanning wide-band phased array antennas

    Författare :Anders Ellgardt; Martin Norgren; Lars Josefsson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical engineering; Elektroteknik;

    Sammanfattning : This thesis considers problems related to the design and the analysis of wide-angle scanning phased arrays. The goals of the thesis are the design and analysis of antenna elements suitable for wide-angle scanning array antennas, and the study of scan blindness effects and edge effects for this type of antennas. LÄS MER

  3. 2. Optical characterization of wide band gap materials by spectroscopic ellipsometry

    Författare :O. P. Alexander Lindquist; Linköpings universitet; []
    Nyckelord :Wide Band Gap materials; ellipsometry; SiC; GaN;

    Sammanfattning : Spectroscopic ellipsometry has been employed in the study of wide band gap materials. Ellipsometry is based on the study of changes in the polarization state of light upon reflection on a surface. LÄS MER

  4. 3. Modelling of wide-band ionospheric HF channels

    Författare :Richard Lindström; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomi; Praktisk;

    Sammanfattning : .... LÄS MER

  5. 4. Efficient Realizations of Wide-Band and Reconfigurable FIR Systems

    Författare :Zaka Ullah Sheikh; Håkan Håkan Johansson; Oscar Gustafsson; Jeffery Coleman; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Complexity reduction is one of the major issues in today’s digital system designfor many obvious reasons, e.g., reduction in area, reduced power consumption,and high throughput. LÄS MER

  7. 5. Extreme Implementations of Wide-Bandgap Semiconductors in Power Electronics

    Författare :Juan Colmenares; Hans-Peter Nee; Leon M. Tolbert; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cryogenic; Gallium Nitride; Gate Driver; Harsh Environments; High Efficiency Converter; High Temperature; MOSFETs; Normally- ON JFETs; Reliability; Silicon Carbide; Wide-Band Gap Semiconductors; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Wide-bandgap (WBG) semiconductor materials such as silicon carbide (SiC) and gallium-nitride (GaN) allow higher voltage ratings, lower on-state voltage drops, higher switching frequencies, and higher maximum temperatures. All these advantages make them an attractive choice when high-power density and high-efficiency converters are targeted. LÄS MER