Sökning: "THz"
Visar resultat 1 - 5 av 94 avhandlingar innehållade ordet THz.
1. HBV frequency multiplier 2D arrays and application
Sammanfattning : The utilisation of the THz spectrum ( 0.3-3 THz ) is hampered by technological difficulties to generate power at these frequencies. LÄS MER
2. Integration of Planar Antennas with MMIC Active Frontends for THz Imaging Applications
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
3. Superconducting THz mixers based on MgB2 film
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
4. NbN and NbTiN Hot Electron Bolometer THz Mixers
Sammanfattning : 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. LÄS MER
5. Study of MgB2 HEB mixers at THz frequencies
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