Search for dissertations about: "gain bandwidth"

Showing result 1 - 5 of 133 swedish dissertations containing the words gain bandwidth.

2. 1. MgB2 hot-electron bolometer mixers for sub-mm wave astronomy

   Author : Evgenii Novoselov; Chalmers tekniska högskola; []
   Keywords : 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;

   Abstract : 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. READ MORE

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

   Author : Evgenii Novoselov; Chalmers tekniska högskola; []
   Keywords : 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;

   Abstract : 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. READ MORE

5. 3. Bandwidth Efficient IPTV Distribution : On Error Resilience and Fast Channel Change

   Author : Ulf Jennehag; Tingting Zhang; Stefan Pettersson; Nikolaus Färber; Mittuniversitetet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; IPTV distribution; Computer and systems science; Data- och systemvetenskap;

   Abstract : Television is now changing its traditional distribution forms to being distributed digitally over broadband networks. The recent development of broadband Internet connectivity has made the transition to Internet Protocol Television (IPTV) possible. READ MORE

6. 4. Fundamental Bounds on Performance of Periodic Electromagnetic Radiators and Scatterers

   Author : Andrei Ludvig-Osipov; B. Lars G. Jonsson; Christophe Caloz; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Q-factor; bandwidth; antenna arrays; periodic structures; physical bounds; physical limitations; Electrical Engineering; Elektro- och systemteknik;

   Abstract : In this thesis, the optimal bandwidth performance of periodic electromagnetic radiators and scatterers is studied. The main focus is on the development and application of methods to obtain fundamental physical bounds, relating geometrical parameters, frequency bandwidth, efficiency and radiation characteristics of periodic electromagnetic structures. READ MORE

7. 5. Frequency Reconfigurable and Linear Power Amplifiers Based on Doherty and Varactor Load Modulation Techniques

   Author : William Hallberg; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gallium nitride GaN ; wideband; Class-J; linear; microwave; radio frequency RF ; Doherty; broadband; AM AM; silicon carbide SiC ; bandwidth; power amplifier PA ; AM PM; varactor; dynamic load modulation DLM ; fifth generation mobile networks 5G ; energy efficiency;

   Abstract : In future mobile communication networks, there will be a shift towards higher carrier frequencies and highly integrated multiple antenna systems. The system performance will largely depend on the available RF hardware. As such, RF power amplifiers (PAs) with improved efficiency, linearity, and bandwidth are needed. READ MORE