Antenna Shape Synthesis Using Characteristic Mode Concepts

dc.contributor.authorEthier, Jonathan L. T.
dc.description.abstractCharacteristic modes (CMs) provide deep insight into the electromagnetic behaviour of any arbitrarily shaped conducting structure because the CMs are unique to the geometry of the object. We exploit this very fact by predicting a perhaps surprising number of important antenna metrics such as resonance frequency, radiation efficiency and antenna Q (bandwidth) without needing to specify a feeding location. In doing so, it is possible to define a collection of objective functions that can be used in an optimizer to shape-synthesize antennas without needing to define a feed location a priori. We denote this novel form of optimization “feedless” or “excitation-free” antenna shape synthesis. Fundamentally, we are allowing the electromagnetics to dictate how the antenna synthesis should proceed and are in no way imposing the physical constraints enforced by fixed feeding structures. This optimization technique is broadly applied to three major areas of antenna research: electrically small antennas, multi-band antennas and reflectarrays. Thus, the scope of applicability ranges from small antennas, to intermediate sizes and concludes with electrically large antenna designs, which is a testament to the broad applicability of characteristic mode theory. Another advantage of feedless electromagnetic shape synthesis is the ability to synthesize antennas whose desirable properties approach the fundamental limits imposed by electromagnetics. As an additional benefit, the feedless optimization technique is shown to have greater computational efficiency than traditional antenna optimization techniques.
dc.publisherUniversité d'Ottawa / University of Ottawa
dc.subjectCharacteristic Mode
dc.subjectElectrically Small Antenna
dc.subjectMulti-band Antenna
dc.subjectAntenna Shape Synthesis
dc.subjectFeedless Shape Synthesis
dc.subjectFragmented Antenna
dc.subjectRadiation Efficiency
dc.subjectResonance Frequency
dc.subjectAntenna Geometry
dc.subjectMobile Phone
dc.subjectSub-Structure Characteristic Modes
dc.subjectPeriodic Structures
dc.subjectTransmission Coefficient
dc.subjectReflection Coefficient
dc.subjectSingle Mode
dc.subjectAntenna Q
dc.titleAntenna Shape Synthesis Using Characteristic Mode Concepts
dc.faculty.departmentScience informatique et génie électrique / Electrical Engineering and Computer Science
dc.contributor.supervisorMcNamara, Derek
dc.embargo.termsimmediateénie / Engineeringénie / Engineering
uottawa.departmentScience informatique et génie électrique / Electrical Engineering and Computer Science
CollectionThèses, 2011 - // Theses, 2011 -

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