Sökning: "mixers"

Visar resultat 1 - 5 av 70 avhandlingar innehållade ordet mixers.

  1. 1. Superconducting THz mixers based on MgB2 film

    Författare :Stella Bevilacqua; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bolometers; IF bandwidth.; superconductors; MgB2; THz Detectors; mixers;

    Sammanfattning : Superconducting NbN hot electron bolometer (HEB) mixers are widely used in terahertz radio astronomy. Such mixers have superior performance compared to SIS and Schottky diode mixers at frequency above 1THz. However, their drawback is a limited IF bandwidth. LÄS MER

  3. 2. Resitive FET Mixers

    Författare :Klas Yhland; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis presents theory, device models and circuits related to resistive FET mixers: A wave analysis for resistive mixers The analysis gives an intuitive estimate of resistive mixer performance when most parameters are unknown. It is based on the assumption that all mixing terms generated in the mixer are terminated with the same impedance. LÄS MER

  4. 3. Study of MgB2 HEB mixers at THz frequencies

    Författare :Evgenii Novoselov; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; noise temperature; mixers; bandwidth; THz detectors; superconductors; bolometers; conversion gain; MgB2;

    Sammanfattning : The terahertz (THz) range is very attractive for astronomical observations. Spectroscopy and photometry of remote space objects in the THz range 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. LÄS MER

  5. 4. Antenna Integrated Superconducting Mixers

    Författare :Hans Ekström; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tapered slotline antenna; mixer; double dipole antenna; superconducting; hot electron; receiver; Niobium; bolometer; trilayer junction; edge junction; Niobium Nitride; SIS;

    Sammanfattning : This thesis investigates the prospects of some different superconducting mixers integrated with planar antennas for the millimeter and submillimeter regime. Two kinds of Superconductor/Insulator/Superconductor (SIS) tunnel junctions for use in mixers have been fabricated; Nb/PbBi edge junctions and Nb trilayer junctions. LÄS MER

  7. 5. 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