Search for dissertations about: "spiral antennas"

Found 2 swedish dissertations containing the words spiral antennas.

  2. 1. Characterization of artificially soft surfaces and their applications in antenna design

    Author : Zhinong Ying; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dipole antenna; UTD; GPS; broadband antennas; circular polarization; feed; moment method; soft and hard surfaces; surface impeddance; corrugated horn; antennas; multipath effect; microstrip antenna; magnetic coating; spiral antenna; corrugated surface; dielectric loaded surface; ground plane; slot antenna; monopole antenna; helical antenna; choke-ring;

    Abstract : .... READ MORE

  4. 2. NbN and NbTiN Hot Electron Bolometer THz Mixers

    Author : Pourya Khosropanah; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; receiver noise; hot electron bolometer; superconducting detector; spiral antenna; NbTiN; submillimeter mixer; THz mixer; HEB; FTS; NbN; quasioptical receiver; heterodyne receiver; double slot antenna; twin slot antenna; Fourier Transform Spectrometer;

    Abstract : The thesis reports the development of Hot Electron Bolometer (HEB) mixers for radio astronomy heterodyne receivers in THz frequency range. Part of this work is the fabrication of HEB devices, which are based on NbN or NbTiN superconducting thin films (≤5 nm). They are integrated with wideband spiral or double-slot planar antennas. READ MORE