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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

Prism-coupled square optical micropillar resonator-based filters for optical communications /

Lee, Ho Tong. January 2004 (has links)
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 134-138). Also available in electronic version. Access restricted to campus users.
82

Thin-film piezoelectric-on-substrate resonators and narrowband filters

Abdolvand, Reza. January 2008 (has links)
Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Farrokh Ayazi; Committee Member: James D. Meindl; Committee Member: John D. Cressler; Committee Member: Nazanin Bassiri-Gharb; Committee Member: Oliver Brand.
83

Monte Carlo simulation of squeeze-film air damping on micro resonators in the free-molecule regime /

Hong, Gang. January 2010 (has links)
Includes bibliographical references (p. 59-64).
84

Application of the microwave Fabry-Perot resonator to plasma diagnostics

Chaffin, R. J. January 1977 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
85

An experimental and computational investigation of dielectrics for use in quarter wave coaxial cavity resonators

Lowery, Andrew D. January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xii, 153 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 133-135).
86

Circular microresonator cross-connect filters and hexagonal microresonator add-drop filters in silicon nitride /

Zheng, Shengmei. January 2005 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 115-121). Also available in electronic version.
87

Optical resonators and quantum dots and excursion into quantum optics, quantum information and photonics /

Bianucci, Pablo, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
88

Surface plasmon resonance-assisted coupling to whispering-gallery modes in micropillar resonators and silicon microdisk-based depletion-type modulators using integrated schottky diodes /

Hon, Kam Yan. January 2007 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 97-101). Also available in electronic version.
89

Ceramic coaxial resonator filter in a CubeSat system

Bakam Nguenouho, Odette Sandrine January 2017 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2017. / RF and microwave filters can be implemented using ceramic coaxial resonators. This technology has been widely employed in nanosatellite communications systems recently, owing to its large quality factor (Q), permitting them to have low loss and narrow bandwidth. Features such as high selectivity, high power handling, excellent rejection, and low passband insertion loss are just a few of the key performance areas offered by ceramic coaxial resonators. This feature makes them suitable for use in bandpass filters. Applications with demanding specifications requiring low volume and mass make use of this technology. Fulfilling the required performance goals can be challenging, given the size and weight restriction. Difficulties such as finding the correct length of resonators and the coupling capacitors’ structure to meet the size restriction, limit the type of ceramic coaxial resonators to use. This thesis presents the design of a bandpass filter using ceramic coaxial resonators, which provides evidence of the concept for F’SATI’s future needs. This design will be used in an imminent space mission and the intention is to mount the bandpass filter in the receiver communications system. An intensive investigation was conducted into the use of filters for nanosatellite communication systems. The Chebyshev LC ladder low pass prototype was used to derive the conventional bandpass filter. Thereafter, the coupled resonator bandpass filter was derived using the conventional bandpass filter topology combined with the admittance inverter. Following this, using the ceramic coaxial resonators datasheet and information provided by the manufacturers, the coupled resonator bandpass filter was converted into a 3D model for further simulations, using CST Microwave Studio®. The ceramic coaxial resonator filter fabricated using Rogers’s material provided satisfactory results at its operating frequency between 2.2 GHz and 2.3 GHz. A radiation level test was performed on the filter to justify the use of the metallic enclosure. The test presented a low level of radiation measured at the filter operating frequency (2.25 GHz). The filter was also subjected to temperature cycling. / French–South African Institute of Technology (F’SATI) National Research Foundation (NRF)
90

Electromagnetic design of integrated resonator-transformers

Strydom, Johan Tjeerd 26 February 2009 (has links)
D.Ing. / In the field of power electronics, the relentless demand for higher efficiencies, lower costs and ever-decreasing volume and profile have driven the development of many innovative technologies. Planarization and hybridization have become a substantial part of present system integration methodology. With the subsequent size reduction, the effects of layout and component parasitics are becoming vital issues in the development of innovative structures. The component ‘parasitics’ can be considered dimensional effects of the component structure that are not considered during the design process. The concept of electromagnetic integration is aimed at the utilization and modification of these dimensional effects. This leads to an integrated structure that fulfills multiple electromagnetic functions with the potential for improved power density, efficiency and reliability. In this dissertation, a family of electromagnetically integrated passives is presented. The related electromagnetic modeling and design approach of these complex electromagnetic structures is presented through a case study of L-L-C-T structures. The development of a sufficiently accurate, yet simplified electromagnetic model for design purposes is presented for the case study. With the electromagnetic model as basis, a comprehensive electromagnetic loss model is created. The electromagnetic design and loss models are combined into a design evaluation program. The graphical output of this design evaluation program allows for rapid selection of improved designs based on external cost criteria. This led to numerous insights into the relationships between the design variables. Through modification of the program, some fundamental limits of the integration approach are addressed. A case study design for a 1MHz, 500W dc-dc converter was considered to evaluate the design program. To assess the accuracy of the electromagnetic modeling, three L-L-C-T prototypes are constructed and experimentally tested. The construction process presented improved power density by 80% over previous processes. The electromagnetic component parameters for three prototypes were within 10% of the required design values, while the electromagnetic loss model estimations were within measurement error. The design evaluation program was enlisted in the design of two of these prototypes. This resulted in a 100% further improvement in power density (480W/in3 or 29.3W/cm3) compared to the original prototype without a loss in efficiency.

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