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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Optimization of a helicon plasma source for maximum density with minimal ion heating

Balkey, Matthew M. January 2000 (has links)
Thesis (Ph. D.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains v, 127 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 94-98).
192

Digital implementation of direction-of-arrival estimation techniques for smart antenna systems

Abusultan, Monther Younis. January 2010 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2010. / Typescript. Chairperson, Graduate Committee: Brock LaMeres. Includes bibliographical references (leaves 92-96).
193

Broadband beamforming and direction finding using concentric ring array

Li, Yunhong. January 2005 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2005. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (July 18, 2006) Vita. Includes bibliographical references.
194

The impact of antenna and RF system characteristics on MIMO system capacity /

Morris, Matthew Leon, January 2005 (has links) (PDF)
Thesis (Ph. D.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2005. / Includes bibliographical references (p. 109-116).
195

Reducing threshold of biexciton formation in semiconductor nanocrystals through their self-assembly into nano-antennae /

Emara, Mahmoud M. January 2008 (has links)
Thesis (Ph.D.)--Ohio University, June, 2008. / Abstract only has been uploaded to OhioLINK. Includes bibliographical references (leaves 199-209)
196

Relay-assisted communication fundamental limits and selection strategies /

Lo, Caleb K., January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references and index.
197

X-band antenna design for nano-satellite applications

Maqina, Sinamandla Mvuyisi January 2018 (has links)
Thesis (Master of Engineering in Electrical Engineering)--Cape Peninsula University of Technology, 2018. / This research report discusses feasible designs of conformal antennas that provide a proof of concept for the French South African Institute of Technology’s future needs. The design is to be used in forthcoming space missions and the intention is to mount the antenna on the surface of a spacecraft. Hence, a low profile is mandatory along with good circular polarisation radiation characteristics. Microstrip patch antennas have been chosen for this purpose simply because they have low profile and conform to most structures, thus fulfilling the requirements stated above. All the designs that are featured in this thesis were modelled and validated using the electromagnetic simulation software FEKO and prototypes were built and tested. The simulations and measured results are supplemented by theory. Sometimes it can be challenging to design and develop an antenna that fulfils the required performance goals given the size and weight restrictions that are specified for nano-satellite technology. Therefore, the first phase of this project finds a good balance between the criteria set for CubeSat platforms and antenna performance. The second phase is validation. Single patch antennas and a sequential rotated patch array were designed, built and tested. The sequential rotated patch array offers considerable improvements in performance when compared to single patch antennas. For instance, the 3 dB axial ratio bandwidth increased to 9.6 % from 2 % when a sequential rotated array was used. The CubeSat normally flies in the inclined regions of the low Earth orbit (LEO). This area has high-energy auroral electron fluxes, in which the high-density electrons build up on ungrounded surfaces of spacecraft and cause discharge arcing. The discharge can affect the satellite operation and, in the worst case, cause permanent damage to the components. A mitigation technique by means of a bleeding path provides a quick route to ground and the space-qualified material that is used will ensure that the antenna is robust enough to survive this.
198

Low profile pattern reconfigurable square loop antenna

Pal, Arpan January 2013 (has links)
No description available.
199

Implementation of a wideband microstrip phased array antenna for X-band radar applications

Davids, Vernon Pete January 2009 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009 / This thesis presents the design, analysis and implementation of an eight-element phased array antenna for wideband X-band applications. The microstrip phased array antenna is designed using eight quasi-Yagi antennas in a linear configuration and is printed on RT/Duroid 6010LM substrate made by Rogers Corporation. The feeding network entails a uniform beamforming network as well as a non-uniform -25 dB Dolph-Tschebyscheff beamforming network, each with and without 45° delay lines, generating a squinted beam 14° from boresight. Antenna parameters such as gain, radiation patterns and impedance bandwidth (BW) are investigated in the single element as well as the array environment. Mutual coupling between the elements in the array is also predicted. The quasi-Yagi radiator employed as radiating element in the array measured an exceptional impedance bandwidth (BW) of 50% for a S11 < -10 dB from 6 GHz to 14 GHz, with 3 dB to 5 dB of absolute gain in the frequency range from 8 GHz to 11.5 GHz. The uniform broadside array measured an impedance BW of 20% over the frequency band and a gain between 9 dB to 11 dB, whereas the non-uniform broadside array measured a gain of 9 dB to 11 dB and an impedance BW of 14.5%. Radiation patterns are stable across the X-band. Beam scanning is illustrated in the E-plane for the uniform array as well as for the non-uniform array.
200

Design and analysis of a folded meander dipole antenna using the MININEC program

Barros, Pedro A. 30 May 1991 (has links)
The Mini-Numerical Electromagnetic Code (MININEC) program, a PC-Compatible version of the powerful NEC program, is used to design a new type of reduced-size antenna. The validity of the program to model simple well-known antennas, such as dipoles and monopoles, is first shown. More complex geometries such as folded dipoles, and meander dipole antennas are also analysed using the program. The final design geometry of a meander folded dipole is characterized with MININEC, yielding results that serve as the basis for the practical construction of the antenna. Finally, the laboratory work with a prototype antenna is described, and practical results are presented.

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