Sökning: "heterodyne receiver"

Visar resultat 11 - 15 av 17 avhandlingar innehållade orden heterodyne receiver.

  1. 11. Mm-wave Radio Astronomy Instrumentation for the Onsala Space Observatory and SEST

    Författare :Nicholas D. Whyborn; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mm-wave receiver; phase retrieval holography; focal plane imaging array; radio astronomy instrumentation; SIS mixer;

    Sammanfattning : The thesis presents work done in developing instrumentation for mm- and submm-wave radio astronomy. The work described is in several fields. The greater part of the thesis is concerned with sensitive heterodyne receivers and in particular the cryogenically cooled mixers. In paper A the SEST telescope and its observing system are described. LÄS MER

  3. 12. Radioastronomy Instrumentation for Herschel and APEX Projects

    Författare :Miroslav Pantaleev; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; beam measurements; quasioptics; optical alignment; submillimeter; HEB mixer;

    Sammanfattning : This thesis presents work done in developing instrumentation for sub-mm radio astronomyprojects.The first part covers Gaussian beam measurements for the Heterodyne Instrument for Far-Infrared (HIFI) of the Herschel Space Observatory project by the European Space Agency. LÄS MER

  4. 13. Design Of Dual Polarisation Sideband Separation Mixer For ALMA Band 5

    Författare :Bhushan Billade; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Millimeter wave receivers; Millimeter wave mixers; Superconductor-Insulator-Superconductor mixers; Thin film circuits.; Quasiparticle mixers;

    Sammanfattning : This licentiate is focused on the design and development of Superconductor-Insulator-Superconductor (SIS) junction mixer for ALMA Band 5, one of the ten frequency bands of the Atacama Large Millimeter Array (ALMA) project. ALMA Band 5 is a dual polarisation sideband separation heterodyne receiver covering radio frequencies (RF) from 163 GHz to 211 GHz, with 4-8 GHz intermediate frequency (IF). LÄS MER

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

    Författare :Evgenii Novoselov; Chalmers tekniska högskola; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  7. 15. Integration of Planar Antennas with MMIC Active Frontends for THz Imaging Applications

    Författare :Yogesh Karandikar; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sub-Harmonic Resistive Mixer; Planar Antennas; Gaussian Coupling; MMIC; Gilbert Cell Mixer; THz;

    Sammanfattning : In recent years, there has been constant growth in using THz frequencies or mm, sub- mm wavelengths for various applications such as: Astronomy, Atmospheric studies, security, bio-medical imaging. All these applications are now seen more feasible due to rapid enhancements of semi-conductor processing technologies. LÄS MER