Sökning: "high power microwave"

Visar resultat 1 - 5 av 128 avhandlingar innehållade orden high power microwave.

  1. 1. High Power Microwave Sources : design and experiments

    Författare :Cecilia Möller; Nils Brenning; Stefan Silfverskiöld; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space physics; Rymdfysik; Plasma physics; Plasmafysik;

    Sammanfattning : High-Power Microwaves (HPM) can be used to intentionally disturb or destroy electronic equipment at a distance by inducing high voltages and currents. This thesis presents results from experiments with a narrow band HPM source, the vircator. LÄS MER

  3. 2. SiC Varactors for Dynamic Load Modulation of Microwave Power Amplifiers

    Författare :Christer Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear characterization; varactors; active load-pull; power; microwave; amplifier; dynamic load modulation; SiC; energy efficiency;

    Sammanfattning : The rapid consumer adoption of mobile services is leading to an exponential growth in wireless data traffic. In order to accommodate more concurrent high data-rate users, the required complexity of transmitting radio base station (RBS) power amplifiers (PAs) is increasing. LÄS MER

  4. 3. Device Technology Based on High Temperature Superconductors and Microwave Breakdown in Gases

    Författare :Martin Löfgren; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; distortion; penetration depth; surface resistance; transmit-receive switch; coupled-grain model; high-power; microwave; pulse; surface impedance; breakdown; propagation; modulator; air; superconductor; transmission line; resonator; coplanar waveguide; plasma;

    Sammanfattning : This thesis deals with two separate fields of microwave technology. The first section treats microwave characterization and applications of high temperature superconducting (HTS) thin films, while the second section treats microwave breakdown in transmit-receive (TR) switches and in air. Within the first section, four main topics are adressed. LÄS MER

  5. 4. Theory and Design of Wideband Doherty Power Amplifiers

    Författare :David Gustafsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Doherty; gallium nitride; GaN; power amplifier; MMIC; microwave; Broadband amplifiers; high efficiency; wideband;

    Sammanfattning : The Doherty power amplifier (DPA) is one of the most popular power amplifier architectures for obtaining high average efficiency for modern communication signals with high peak-to-average power ratios (PAPR). However, the DPA suffers from often having narrowband performance which limits its capabilities in wideband and/or multi-standard microwave and radio frequency applications. LÄS MER

  7. 5. Silicon Carbide Microwave Devices

    Författare :Joakim Eriksson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SBD; high-power microwave devices; Silicon Carbide; diode mixer; wide band gap devices; physical simulations; resistive mixer; microwave devices; MESFET; Schottky diode;

    Sammanfattning : This work deals with silicon carbide (SiC) microwave devices. It treats two devices; the Schottky diode and the metal semiconductor field effect transistor (MESFET). Different MESFET materials, fabrication processes, theoretical models for physical simulation, and device models are presented. LÄS MER