Search for dissertations about: "radio receiver"

Showing result 21 - 25 of 156 swedish dissertations containing the words radio receiver.

  2. 21. Development of a Sideband Separating SIS Mixer Technology for MM-Wavelengths

    Author : Vessen Vassilev; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mm-wave receiver; SIS mixer; radio astronomy instrumentation; waveguide to microstrip transition; sideband separation receiver;

    Abstract : This thesis presents work done in developing instrumentation for mm-wave radio astronomy. The main subject of the thesis is a sideband separating (2SB) receiver for 85-115 GHz based on a quadrature scheme with two identical SIS mixer junctions pumped by a LO applied with 90° phase difference. READ MORE

  4. 22. Antenna Integrated Superconducting Mixers

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

    Abstract : 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. READ MORE

  5. 23. Spectrometers and receiver systems for ground, balloon and satellite based (sub)millimetre radio astronomy

    Author : Anders Emrich; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; subsystem standards; spectrometer design; autocorrelator; sub millimetre wavelength radio;

    Abstract : .... READ MORE

  6. 24. Ultra-wideband feed design and characterization for next generation radio telescopes

    Author : Jonas Flygare; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; reflector feed; geodesy; radio astronomy; quad-ridge flared horn; square kilometre array; dielectric loading; spline-defined; decade bandwidth; Ultra-wideband antennas;

    Abstract : Radio telescopes are used as tools for observations in both radio astronomy and geodesy. To observe the weak sources in space, highly sensitive receivers headed by optimized reflector feeds are needed. Wideband and ultra-wideband (UWB) receiver systems enable large continuous frequency bandwidth and reduce the number of receivers that are needed. READ MORE

  7. 25. Design and Performance of Some Components for a Millimeter Wave Imaging Receiver

    Author : Guillermo F. Delgado Gunckel; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nipi MQW; imaging receiver; lens shaping; diplexer; kinoform; opto-electronic quasi-optical modulation; dielectric lenses; sideband filter; diffractive optics;

    Abstract : This thesis deals with the design and performance of some novel devices for an imaging receiver, operating in the frequency band centered at 100 GHz, to be used in radio astronomy research. The emphasis is given on simple, small and reliable devices in order to reduce the complexity of an already complex receiver. READ MORE