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Modeling and design of compact microwave components and systems for wireless communications and power transmissionZepeda, Paola 30 September 2004 (has links)
The contribution of the work here presented involves three main topics: Wireless Power Transmission (WPT) technology, phased array systems, and microwave components design and modeling. The first topic presents the conceptual design of a WPT system at 2.45GHz with 90% efficiency and 1MW of DC output power. Second, a comparative study between 2.45 and 35GHz WPT operation is provided. Finally, the optimization of a taper distribution with reduced thermal constraints on a sandwich transmitter is realized. For a 250- and 375-m antenna radius, 89.7% of collection efficiency with 29% reduction in maximum power density (compared to the Gaussian), and 93% collection efficiency with 39% reduction of maximum power density, are obtained respectively with two split tapers. The reduction in maximum power density and the use of split taper are important to alleviate the thermal problems in high power transmission.
For the phased array project, the conceptual design of a small-scale system and in-depth analysis using two main approaches (statistical and field analysis) is realized. Practical aspects are addressed to determine the phased array main design features. The statistical method provides less accurate results than the field analysis since it is intended for large arrays. Careful theoretical analysis led to good correlation between statistical, field analysis and experimental results.
In the components chapter, efficient loop transitions used in a patch antenna array are designed at K- and W-band. Measured insertion loss (IL) K-band loop is under 0.4dB. The K- and W-band antenna array measured broadside gains are 23.6dB at 24.125GHz and 25dB at 76.5GHz with return loss under 9.54dB from 24 to 24.4GHz and 12 dB from 75.1 to 77.3GHz, respectively. Also, a multilayer folded line filter is designed at 5.8GHz and compared to planar ring filters. Improved measured bandwidth from 2GHz to 7.5GHz and IL of 1.2dB are obtained with approximately half the size of a planar ring resonator. Thirdly, a simplified switch model is implemented for use in broadband phased-shifters. The model presents very good fit to the measured results with an overall total error under 3%, magnitude error less than 8%, and phase errors less than ±0.4°.
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Impact of Mutual Coupling among Antenna Arrays on the Performance of the Multipath Simulator SystemRamamoorthy, Dhayalini January 2014 (has links)
This thesis work presents a study on the impact of mutual coupling among antenna arrays on the performance of the multipath simulator (MPS) system. In MIMO systems, it is a wellknown fact that the mutual coupling significantly affects their system performance. The impact of mutual coupling on MIMO system performance is an important consideration for compact antenna arrays. Hence, it is very important to investigate the impact of mutual coupling on the accuracy of measurements in a MPS system. In this project, the impact of coupling within the MPS array antennas is addressed by performing simulations based on the proposed MPS scattering model which fulfills the far-field (Fraunhoferdistance) boundary conditions. The coupling phenomenon within the MPS array antennas is studied by designing a uniform circular array (UCA) of radius,R consisting of NMPS antennas with single device under test (DUT) antenna at the center. The elements of the array are matched half-wave dipole antennas and the phase of the array elements is kept constant throughout. In this work it is assumed that all the elements in the array are identical and located in the far-field region. This study is carried out by performing MPS simulations in HFSS at the LTE-A band of 2.6GHz. The approach used to model the entire system is by comparing the S-parameters (S21: Forward transmission coefficient parameter) between various array configuration. The simulation results suggest that the impact of mutual coupling increases with the number of MPS antennas and decreases with the radius of the MPS ring. Theradiated power is also measured with and without mutual coupling. Finally, it is concluded that the impact of coupling within the MPS antennas is best countered by designing a large MPS system (preferably R = 10λ or greater), despite the higher incurred costs.
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Development of Flexible-Based Electrode Array for Spinal Cord InterfaceKhaled, Imad M. Unknown Date
No description available.
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Optically interconnected parallel processor arraysDrabik, Timothy J. 12 1900 (has links)
No description available.
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Analysis and design of cylindrically conformable microwave phased array antennas for hyperthermia applicationsNajafabadi, Reza M. 05 1900 (has links)
No description available.
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Design of an FPGA based parallel architecture processor for displaying CSG volumes and surfacesCevik, Ulus January 1996 (has links)
No description available.
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Entwicklung und Implementierung von Auswertungswerkzeugen für Hochdurchsatz-DNA-Kopienzahl-Analysen und deren Anwendung auf LymphomdatenKreuz, Markus 23 March 2015 (has links) (PDF)
Aberrationen in der DNA-Kopienzahl sind häufige genetische Veränderungen bei malignen Lymphomerkrankungen. Zugewinne sowie Deletionen stellen dabei Mechanismen zur Onkogen-Aktivierung sowie Tumorsuppressorgen-Inaktivierung dar und tragen somit zur Pathogenese der Erkrankung bei. Array-CGH und SNP-Array sind Messplattformen, die die genomweite Bestimmung von Kopienzahlaberrationen in einem Experiment ermöglichen. Die bei der Analyse entstehenden Datensätze sind komplex und erfordern automatische Methoden zur Unterstützung der Analyse und Interpretation der Messergebnisse.
In dieser Promotionsarbeit wurden Methoden entwickelt, welche die Analyse von Array-CGH- und SNP-Array-Messungen ermöglichen. Diese Methoden wurden für die Auswertung umfangreicher Datensätze von malignen Non-Hodgkin-Lymphomen verwendet. Dabei wurden Lymphome der Entitäten Burkitt-Lymphom, diffus großzelliges B-Zell-Lymphom, Mantelzelllymphom, primäres ZNS-Lymphom und peripheres T-Zell-Lymphom – nicht anderweitig spezifiziert – analysiert. Für die untersuchten Lymphom-Entitäten konnten hierbei zahlreiche neue rekurrente Kopienzahlaberrationen sowie uniparentale Disomien gezeigt werden, die neue Einblicke in die Pathogenese der jeweiligen Erkrankungen erlauben.
Darüber hinaus erfolgte ein Vergleich beider Messplattformen anhand eines Datensatzes mit gepaarten Array-CGH- und SNP-Array-Daten. Für die eingesetzten Plattformen (2800k-BAC-Array vs. Affymetrix 250k-Sty-SNP-Array) konnte eine circa zwölffach höhere effektive Auflösung der SNP-Array-Plattform gezeigt werden. Die wesentlichen Ergebnisse dieser Arbeit sind in sieben Publikationen eingeflossen.
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Design and development of a vibrotactile stimulator array for the fingertipChanter, Craig Michael January 1999 (has links)
No description available.
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Genetic programming in hardwareMartin, Peter N. January 2003 (has links)
No description available.
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Dynamically reconfigurable intellectual property coresMacBeth, John Stuart January 2003 (has links)
No description available.
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