Search for dissertations about: "dipole antenna"

Showing result 16 - 20 of 27 swedish dissertations containing the words dipole antenna.

2. 16. Photonic terahertz-wave generation, radiation and quasioptical integration

   Author : Biddut Kumar Banik; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; semiconductor device modelling; semiconductor diodes; III-V semiconductors; Catadioptric lens; imaging; dipole antennas; slot antennas; lens antennas; semiconductor heterojunctions; dielectric loaded antennas; optical mixers; photomixers; near-field imaging; computer aided engineering; indium compounds; millimetre wave imaging; near-field optics; submillimeter wave generation; photodiodes; terahertz sources; millimetre wave generation; submillimetre wave integrated circuits; microwave imaging; uni-travelling-carrier photodiodes;

   Abstract : This thesis deals with the uni-travelling-carrier photodiode (UTC-PD) based photonic generation of terahertz waves, antenna designs for the terahertz radiation and a novelcatadioptric lens for quasioptical integration.The ongoing and accomplished research work on the UTC-PD, its limitations and optimisation scopes for attaining higher bandwidth and higher output power have been discussed. READ MORE

4. 17. Dual Band Prime Focus Feed for Satellite Earth Terminals

   Author : Yogesh Karandikar; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reflector Antenna; Choke Horn; Eleven Feed; satellite earth terminals;

   Abstract : Satellite Communication systems have been studied and developed since long. With more high frequency satellite bands coming in the market, there is a need to develop suchsystems with multi-band or wideband operation with reconfigurable antennas which can provide simultaneous transmit receive capabilities on different polarizations as well as have properties suitable to track the satellite. READ MORE

5. 18. Characterization and Enhancement of Antenna System Performance in Compact MIMO Terminals

   Author : Vanja Plicanic; Institutionen för elektro- och informationsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : Co-band multiple-antenna implementation in compact user terminals is necessary for harvesting the full potential of diversity and multiple-input multiple-output (MIMO) technology in cellular communication systems. The recent worldwide deployment of Long Term Evolution (LTE), which requires the use of MIMO technology in the downlink, adds to the urgency of achieving both practical and optimal multiple-antenna systems in user terminals. READ MORE

6. 19. Phased-Array-Fed Reflector Antenna Systems for Radio Astronomy and Earth Observations

   Author : Oleg Iupikov; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : Dense Phased Array Feeds (PAFs) for reflector antennas have numerous advantages over traditional cluster feeds of horns in a one-horn-per-beam configuration, especially in RF-imaging applications which require multiple simultaneously formed and closely overlapped beams. However, the accurate analysis and design of such PAF systems represents a challenging problem, both from an EM-modeling and beamforming optimization point of view. READ MORE

7. 20. Digital Beamforming Focal Plane Arrays for Radio Astronomy and Space-Borne Passive Remote Sensing

   Author : Oleg Iupikov; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; beamforming; spaceborne radiometers; radio telescopes; phased array feeds; reflector antenna feeds; feed-reflector interaction;

   Abstract : Dense Phased Array Feeds (PAFs) for reflector antennas have numerous advantages over traditional cluster feeds of horns in a one-horn-per-beam configuration, especially in RF-imaging applications which require multiple simultaneously formed and closely overlapping beams. However, the accurate analysis and design of such PAF systems represents a challenging problem, both from an EM-modeling and beamforming optimization point of view. READ MORE