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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.
81

A UTD ray description for the collective fields radiated by large antenna phased arrays on a smooth convex surface

Janpugdee, Panuwat, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 173-177).
82

Multiple array schemes for achieving high capacity and high diversity gains in wireless MIMO systems /

Sfar, Sana. January 2005 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 98-101). Also available in electronic version.
83

Jamming mitigation through collaboration

Moon, Jang-Wook. January 2005 (has links)
Thesis (Ph. D.)--University of Florida, 2005. / Title from title page of source document. Document formatted into pages; contains 89 pages. Includes vita. Includes bibliographical references.
84

Antenna and algorithm design in MIMO communication systems exploiting the spatial selectivity of wireless channels /

Forenza, Antonio. January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
85

Phase-shifting techniques for wireless multiple-antenna transmitter applications /

Chu, Min, January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 99-103).
86

Wideband meandering probe-fed patch antenna /

Lai, Hau Wah. January 2005 (has links) (PDF)
Thesis (Ph. D.)--City University of Hong Kong, 2005. / "Submitted to Department of Electronic Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy." Includes bibliographical references (leaves 144-153).
87

Indoor MIMO channels with polarization diversity measurements and performance analysis /

Anreddy, Vikram R. January 2006 (has links)
Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2006. / Ingram Mary Ann, Committee Chair ; Durgin, Gregory David, Committee Member ; Williams, Douglas B, Committee Member.
88

Development of novel approaches for high resolution direction of arrival estimation techniques

Balasubramanian, R. K. January 2016 (has links)
This thesis presents the development of MUSIC algorithm based novel approaches for the estimation of Direction of Arrival (DOA) of electromagnetic sources. For the 2D-DOA estimation, this thesis proposes orthogonally polarized linear array configuration rather than the conventionally invoked two dimensional array. An elegant one dimensional search technique to compute 2D-DOA estimation for a single source scenario has been proposed. To facilitate one dimensional search for 2D-DOA estimation, a closed form relationship between the azimuth and elevation angles of the 2D-DOA is derived using the analytical expressions of radiation patterns of Rectangular Waveguide (RWG) and Circular Waveguide (CWG). The computation time for the proposed one dimensional search technique is reduced by a factor of 50 and 150 for 1 and 0:5 search interval respectively. To improve the accuracy and the resolution of 2D-DOA estimation in case of closely spaced sources, this thesis proposes novel array configurations such as orthogonally polarized planar array, orthogonally mounted linear array and orthogonally polarized linear array. Through numerous simulation studies, a relative performance comparison of 2D-DOA estimation realized through various proposed novel array configurations has been carried out to highlight the accuracy and resolution under wide range of SNR conditions. The thesis presents a discussion on the analysis of effect of spatial de correlation in lieu of the employed orthogonally polarized elements in the array configuration on the improved accuracy and resolution of the 2D-DOA estimation. This thesis also deals with the utility of the proposed orthogonally polarized array configurations for tracking of 2D-DOA angles of non-stationary signal sources. The weighting factor and forgetting factor approaches for smoothing the time-varying covariance matrix of the non-stationary sources are studied. The simulation studies on 2D-DOA tracking by invoking proposed array configurations along with the proposed smoothing techniques prove that orthogonal polarized array configuration track the DOA source angle with minimum estimation errors. The thesis proposes the replacement of computationally intensive numerical schemes in Multiple Signal Classification (MUSIC) algorithm such as eigen decomposition and singular value decomposition with the subspace tracking techniques such as Bi-Iterative Singular Value Decomposition (Bi-SVD) algorithm. Invoking the concept of sub-band processing, the thesis addresses the validity of the extension of the presented 2D-DOA estimation analysis to wide band signal. A two subband filter approach is proposed for the estimation 2D-DOA of single and two wideband sources. The simulation study of the two subband filter approach along with the orthogonal polarized array configurations confirms the better estimation accuracy as well as the lesser computation time.
89

Seinverwerkingsaspekte van akoestiese rignetantennas vir Doppler anemometrie

Meyer, Johan 13 February 2014 (has links)
M.Ing. / Please refer to full text to view abstract
90

Development of self and mutual impedance theory to analyse arrays comprising half wave dipole and folded dipole elements.

Clark, Alan, Robert January 1993 (has links)
A thesis submitted to the Faculty of Engineering,University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree or Doctor of Philosophy. / The aim of the thesis is to develop techniques for the analysis of antennas composed of dipoles and folded dipoles,that are efficient relative to the method-of-moments. (Abbreviation abstract) / AC2017

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