Search for dissertations about: "noise temperature"

Showing result 11 - 15 of 240 swedish dissertations containing the words noise temperature.

  2. 11. Development of a Noise-Based Method for the Determination of the Moderator Temperature Coefficient of Reactivity (MTC) in Pressurized Water Reactors (PWRs)

    Author : Christophe Demaziere; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; point-kinetics; Decay Ratio DR ; Gamma-Thermometer GT ; temperature noise structure of the ; correlation length; boron dilution method; noise analysis; core calculations; dynamic reactor transfer function; moderator temperature coefficient MTC ;

    Abstract : The Moderator Temperature Coefficient of reactivity (MTC) is an important safety parameter of Pressurized Water Reactors (PWRs). In most countries, the so-called at-power MTC has to be measured a few months before the reactor outage, in order to determine if the MTC will not become too negative. READ MORE

  4. 12. RF and Noise Optimization of Pseudomorphic inP HEMT Technology

    Author : Mikael Malmkvist; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fabrication; high electron mobility transistor HEMT ; optimization; Schottky layer; InAlAs; Indium phosphide InP ; MMIC.; noise; pseudomorphic; modeling; InGaAs;

    Abstract : The InGaAs-InAlAs-InP high electron mobility transistor (InP HEMT) is the electronic device utilized for the highest frequency and/or the lowest noise applications known to date for analog transistor-based circuits. Hence it is of both scientific and technological interest to explore the InP HEMT for even further improvement in device performance. READ MORE

  5. 13. MgB2 hot-electron bolometer mixers for sub-mm wave astronomy

    Author : Evgenii Novoselov; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; hot-electron bolometer; gain bandwidth; noise bandwidth; thin film; electron-phonon interaction; noise temperature; THz detector; conversion gain; mixer; magnesium diboride; superconductor;

    Abstract : Spectroscopy and photometry in the terahertz (THz) range of remote space objects allows for a study of their chemical composition, because this range covers rotational lines from simple molecules and electron transition lines from atoms and ions. Due to high spectral resolution, THz heterodyne receivers al- low for studying dynamical properties of space objects manifested in doppler-shifted emission lines. READ MORE

  6. 14. InP High Electron Mobility Transistor Design for Cryogenic Low Noise Amplifiers

    Author : Eunjung Cha; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cryogenic; stability; noise temperature; InP HEMT; LNA; MMIC;

    Abstract : The InGaAs/InAlAs/InP high electron mobility transistor (InP HEMT) is the superior technology for the most demanding low-noise and high-speed microwave and millimeter-wave applications, in particular in radio astronomy and deep-space communication. InP HEMT has enabled cryogenic low noise amplifier (LNA) designs with noise temperatures about ten times the quantum noise limit from sub  GHz up to 120 GHz. READ MORE

  7. 15. Studies of acoustic waves, noise and charge pumping using single-electron devices

    Author : Martin Gustafsson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; single-electron pump; single-electron transistor; surface acoustic wave; single-electron devices; charge pumping; TLF; SINIS turnstile; electrometer; two-level fluctuator; single-photon detector; noise; SAW; SET;

    Abstract : This thesis covers a range of experiments on single-electron devices, electrical circuits that utilize the discreetness of the electron charge. The Single-Electron Transistor (SET) is of special importance among these, being the most sensitive electrometer demonstrated, and sufficiently mature to serve as a building block in sensors and detectors for physical phenomena that can be transformed into charge signals. READ MORE