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Dissertations / Theses on the topic 'Surface electromagnetic waves'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Reese, Owein. "Homogenization of acoustic wave propagation in a magnetorheological fluid." Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0430104-101629.

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2

Ailes-Sengers, Lynn H. "Pulse broadening, polarimetric and angular memory effects of wave scattering from very rough surfaces /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/5856.

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3

Lee, Seung-Woo. "Computational electromagnetic approaches for the analysis of rough surface scattering and artificial composite materials /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/5997.

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4

Nagaraj, Nagaraj. "Effects of Dissipation on Propagation of Surface Electromagnetic and Acoustic Waves." Thesis, University of North Texas, 2012. https://digital.library.unt.edu/ark:/67531/metadc115126/.

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With the recent emergence of the field of metamaterials, the study of subwavelength propagation of plane waves and the dissipation of their energy either in the form of Joule losses in the case of electomagnetic waves or in the form of viscous dissipation in the case of acoustic waves in different interfaced media assumes great importance. with this motivation, I have worked on problems in two different areas, viz., plasmonics and surface acoustics. the first part (chapters 2 & 3) of the dissertation deals with the emerging field of plasmonics. Researchers have come up with various designs in an efort to fabricate efficient plasmonic waveguides capable of guiding plasmonic signals. However, the inherent dissipation in the form of Joule losses limits efficient usage of surface plasmon signal. a dielectric-metal-¬dielectric planar structure is one of the most practical plasmonic structures that can serve as an efficient waveguide to guide electromagnetic waves along the metal-dielectric boundary. I present here a theoretical study of propagation of surface plasmons along a symmetric dielectric-metal-dielectric structure and show how proper orientation of the optical axis of the anisotropic substrate enhances the propagation length. an equation for propagation length is derived in a wide range of frequencies. I also show how the frequency of coupled surface plasmons can be modulated by changing the thickness of the metal film. I propose a Kronig-Penny model for the plasmonic crystal, which in the long wavelength limit, may serve as a homogeneous dielectric substrate with high anisotropy which do not exist for natural optical crystals. in the second part (chapters 4 & 5) of the dissertation, I discuss an interesting effect of extraordinary absorption of acoustic energy due to resonant excitation of Rayleigh waves in a narrow water channel clad between two metal plates. Starting from the elastic properties of the metal plates, I derive a dispersion equation that gives resonant frequencies, which coincide with those observed in the experiment that was performed by Wave Phenomena Group at Polytechnic University of Valencia, Spain. Two eigenmodes with different polarizations and phase velocities are obtained from the dispersion equation. at certain critical aperture of the channel, an interesting cutoff effect, which is unusual for an acoustic wave, is observed for one of the eigenmodes with symmetric distribution of the pressure field. the theoretical prediction of the coupling and synchronization of Rayleigh waves strongly supports the experimentally measured shift of the resonant frequencies in the transmission spectra with channel aperture. the observed high level of absorption may find applications in designing metamaterial acoustic absorbers.

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5

Lin, Chien-Min. "Efficiently computational techniques for solving large-scale electromagnetic problems microstrip interconnects and rough surface scattering /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/5878.

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6

Liu, Kexin. "Theoretical Investigation on Propagation and Coupling of Nonreciprocal Electromagnetic Surface Waves." Doctoral thesis, KTH, Elektroteknisk teori och konstruktion, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-190792.

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This thesis aims at revealing the fundamental guiding and coupling properties of nonreciprocal electromagnetic surface waves on magneto-optical or gyromagnetic media and designing novel applications based on the properties. We introduce the background in the first chapter. We then describe the concept of nonreciprocity and the main calculation method in the second chapter. In the third chapter, we show that one-way waves can be sustained at the edge of a gyromagnetic photonic crystal slab under an external magnetic field. We also investigate the coupling between two parallel one-way waveguides. We reveal the condition for effective co-directional and contra-directional coupling. We also notice that the contra-directional coupling is related to the concept of a “trapped rainbow”. In the fourth chapter, we address the concept of a “trapped rainbow”. It aims at trapping different frequency components of the electromagnetic wave packet at different positions in space permanently. In previous structures, the entire incident wave is reflected due to the strong contra-directional coupling between forward and backward modes. To overcome this difficulty, we show that utilizing nonreciprocal waveguides under a tapered external magnetic field can achieve a truly “trapped rainbow” effect at microwave frequencies. We observe hot spots and relatively long duration times around critical positions through simulations and find that such a trapping effect is robust against disorders. Lastly, in the fifth chapter, we study the one-way waves in a surface magnetoplasmon cavity. We find that the external magnetic field can separate the clockwise and anti-clockwise cavity modes into two totally different frequency ranges. This offers us more choices, both in the frequency ranges and in the one-way directions, for realizing one-way components. We also show the waveguide-cavity coupling by designing a circulator, which establishes the foundation for potential applications.<br><p>QC 20160816</p><p></p>

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7

Chen, Yongpin, and 陈涌频. "Surface integral equation method for analyzing electromagnetic scattering in layered medium." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B4775283X.

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Surface integral equation (SIE) method with the kernel of layered medium Green's function (LMGF) is investigated in details from several fundamental aspects. A novel implementation of discrete complex image method (DCIM) is developed to accelerate the evaluation of Sommerfeld integrals and especially improve the far field accuracy of the conventional one. To achieve a broadband simulation of thin layered structure such as microstrip antennas, the mixed-form thin-stratified medium fast-multipole algorithm (MF-TSM-FMA) is developed by applying contour deformation and combining the multipole expansion and plane wave expansion into a single multilevel tree. The low frequency breakdown of the integral operator is further studied and remedied by using the loop-tree decomposition and the augmented electric field integral equation (A-EFIE), both in the context of layered medium integration kernel. All these methods are based on the EFIE for the perfect electric conductor (PEC) and hence can be applied in antenna and circuit applications. To model general dielectric or magnetic objects, the layered medium Green's function based on pilot vector potential approach is generalized for both electric and magnetic current sources. The matrix representation is further derived and the corresponding general SIE is setup. Finally, this SIE is accelerated with the DCIM and applied in quantum optics, such as the calculation of spontaneous emission enhancement of a quantum emitter embedded in a layered structure and in the presence of nano scatterers.<br>published_or_final_version<br>Electrical and Electronic Engineering<br>Doctoral<br>Doctor of Philosophy

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8

Li, Qin. "Numerical simulations of interactions of electromagnetic waves with lossy dielectric surfaces using fast computational methods /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/5848.

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9

Le, Charles Tuan-Cong. "Angular memory effect and its interferometric applications in rough surface mean height profiling /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/6005.

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10

Twardowski, T. "Exact theory of surface-guided TM and coupled TE-TM nonlinear electromagnetic waves." Thesis, University of Salford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381757.

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11

Mason, Sammuel P. "Atmospheric effects on radio frequency (RF) wave propagation in a humid, near-surface environment." Monterey, California : Naval Postgraduate School, 2010. http://edocs.nps.edu/npspubs/scholarly/theses/2010/Mar/10Mar%5FMason.pdf.

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Thesis (M.S. in Meteorology)--Naval Postgraduate School, March 2010.<br>Thesis Advisor(s): Guest, Peter S. ; Goroch, Andreas K. "March 2010." Author(s) subject terms: Electromagnetic propagation, electromagnetic scattering, groundwave propagation, mathematical techniques, variance reduction. Includes bibliographical references (p. 67-68). Also available in print.

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12

Sajjad, Naheed. "Bistatic scattering of electromagnetic waves from rough surface by using second order twoscale model : application to sea and bare soil surface." Brest, 2011. http://www.theses.fr/2011BRES2049.

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The estimation of radar cross section (RCS) of randomly rough surfaces is essential for designing terrain and sea surface remote sensing systems. The particular problem of wave scattering at low grazing angles is of great interest because of its importance for the low-altitude/long-range radar surveillance, target tracking, communication and navigation systems operating at low grazing conditions above the rough surface. The radar cross section from a rough surface becomes very small at grazing incidence, since most part of the incident power is scattered around the specular direction (depending on the degree of surface roughness). Moreover, the dominant scattering mechanisms at low and high grazing angles are different e. G. , the effects of multiple scattering (or higher order scattering), shadowing, fading and mechanisms attributable to wave breaking are particularly marked in the low grazing angle regime. Therefore, in this context the research has been conducted in this thesis. A second order two-scale model (TSM2) has been developed to study the bistatic scattering enhancement at grazing angles and the accurate depolarization estimation in a radar return. The applications of TSM2 are presented for sea and bare soil surfaces. The results obtained from newly developed model are compared with the available experimental data and other models to demonstrate the validity and efficiency of TSM2<br>L’estimation de la surface équivalente radar (SER) des fouillis de mer et terrestre est essentielle pour la conception et l’amélioration des performances des systèmes de télédétection et d’observation de la planète. Le problème particulier de la diffusion des ondes en configuration à angle rasant est de grand intérêt à cause de son importance pour la surveillance, suivi de cible, la communication et les systèmes de navigation fonctionnant au-dessus de surfaces rugueuses, terrestre ou maritime. La surface équivalente radar d’une surface rugueuse devient très faible en incidence rasante puisque la plus grande partie de la puissance incidente est diffusée dans la direction spéculaire (selon le degré de rugosité de k surface). De plus, les mécanismes principaux de diffusion sont différents aux angles rasants, par exemple, les effets de diffusion multiple (ou de diffusion d’ordre supérieur), l’ombrage, fading et les mécanismes liés au déferlement des vagues sont particulièrement présents dans une telle configuration. Par conséquent, c’est dans ce contexte que s’intègre les travaux de recherche développés dans cette thèse. Ceci en développant le modèle deux échelles à l’ordre 2 (TSM2) permettant ainsi de contribuer à l’estimation des coefficients de diffusion bistatique par les surfaces rugueuses avec l’application de ce modèle aux surfaces maritime et terrestre. L’évaluation du modèle développé est réalisée en effectuant des comparaisons par rapport aux résultats obtenus avec d’autres modèles et aussi aux données issues de la littérature ouverte

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13

Jorgenson, Ralph Corleissen. "Surface plasmon resonance based bulk optic and fiber optic sensors /." Thesis, Connect to this title online; UW restricted, 1993. http://hdl.handle.net/1773/5996.

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14

Forslund, Ola. "Scattering and propagation of electromagnetic waves in planar and curved periodic structures - applications to plane wave filters, plane wave absorbers and impedance surfaces." Doctoral thesis, KTH, Alfvén Laboratory, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3825.

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<p>The subject of this thesis is scattering of electromagneticwaves from planar and curved periodic structures. The problemspresented are solved in the frequency domain.</p><p>Scattering from planar structures with two-dimensionalperiodic dependence of constitutive parameters is treated. Theconstitutive parameters are assumed to vary continuously orstepwise in a cross section of a periodically repeating cell.The variation along a longitudinal coordinate z is arbitrary. Ageneral skew lattice is assumed. In the numerical examples, lowloss and high loss dielectric materials are considered. Theproblem is solved by expanding the .elds and constitutiveparameters in quasi-periodic and periodic functionsrespectively, which are inserted into Maxwells equations.Through various inner products de.ned with respect to the cell,and elimination of the longitudinal vector components, a linearsystem of ordinary di.erential equations for the transversecomponents of the .elds is obtained. After introducing apropagator, which maps the .elds from one transverse plane toanother, the system is solved by backward integration.Conventional thin metallic FSS screens of patch or aperturetype are included by obtaining generalised transmission andre.ection matrices for these surfaces. The transmission andre.ection matrices are obtained by solving spectral domainintegral equations. Comparisons of the obtained results aremade with experimental results (in one particular case), andwith results obtained using a computer code based on afundamentally di.erent time domain approach.</p><p>Scattering from thin singly curved structures consisting ofdielectric materials periodic in one dimension is alsoconsidered. Both the thickness and the period are assumed to besmall. The .elds are expanded in an asymptotic power series inthe thickness of the structure, and a scaled wave equation issolved. A propagator mapping the tangential .elds from one sideto the other of the structure is derived. An impedance boundarycondition for the structure coated on a perfect electricconductor is obtained.</p><p><b>Keywords:</b>electromagnetic scattering, periodicstructure, frequency selective structure, frequency selectivesurface, grating, coupled wave analysis, electromagneticbandgap, photonic bandgap, asymptotic boundary condition,impedance boundary condition, spectral domain method,homogenisation</p>

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15

Pak, Kyung. "Studies of large-scale random rough surface scattering problems based on Monte Carlo simulations with efficient computation integral equations methods /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/5941.

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16

Rockway, John Dexter. "Integral equation formulation for object scattering above a rough surface /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/5832.

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17

Henkel, Carsten. "Coherence theory of atomic de Broglie waves and electromagnetic near fields." Thesis, [S.l. : s.n.], 2004. http://pub.ub.uni-potsdam.de/2004/0027/henkel.pdf.

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18

Shinall, Brian Darnell. "Using surface plasmon resonance spectroscopy to characterize thin composite films." Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/10157.

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19

Gill, Eric William. "The scattering of high frequency electromagnetic radiation from the ocean surface : an analysis based on a bistatic ground wave radar configuration /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0003/NQ42476.pdf.

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20

Hidle, Frederick B. "Application of the integral equation asymptotic phase method to penetrable scatterers." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/15797.

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21

Hidalgo, B. Julio Gonzalo. "Feasibility study of surface applications for Flashblast[TM] radiation in the food industry." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/91118.

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This investigation was undertaken to determine if ultra-high intensity radiant energy, can be utilized in the food industry to eliminate or significantly reduce surface contamination. FLASHBLAST™ is the trademark of a pulsed power electromagnetic radiation apparatus developed by Maxwell Laboratories, Inc., San Diego, CA. A FLASHBLAST™ transforms electrical energy into high intensity, short duration pulses of ultraviolet, visible and infrared radiation. FLASHBLAST™ radiation was found to be highly effective in inactivating vegetative cells, fungi and spores. It was also found to be a viable alternative for total or partial inactivation of microbial contamination on food packaging materials. It was found that FLASHBLAST™ radiation is composed of approximately 31.4% of IR, 19.3% of UV and 49.3% of visible radiation. Only the UV spectral bands were responsible for the damage to the microorganisms. Although it was concluded that UV absorption by protein was responsible for most of the organoleptic changes, the data indicated that by filtering the visible and IR regions of the spectrum, the undesirable organoleptic changes in food products were greatly diminished.<br>M.S.

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22

Polat, Ozgur Murat. "Ray Anlaysis Of Electromagnetic Scattering From Semi-infinite Array Of Dipoles In Free Space." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12608347/index.pdf.

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Electromagnetic wave scattering from a semi-infinite array of dipoles in free space is described by using asymptotic high frequency methods. An electric field integral expression is obtained and solved with asymptotic high frequency methods. An asymptotic field expression is obtained for a finite &times<br>infinite array of dipoles in free space. The analytical closed form expression for the array guided surface wave launching coefficient is obtained via a combination of an asymptotic high frequency analysis of a related reciprocal problem and Lorentz reciprocity integral formulation for the semi-infinite planar dipole array in which modified Kirchhoff approximation is used. The accuracy and the validity of the asymptotic analytical solutions are compared with the numerical solutions available in the literature before.

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23

Kosaka, Hiroyuki. "Numerical Studies of the Electromagnetic Fields and Plasma Properties in a Microwave Plasma Source Excited by Azimuthally Symmetric Surface Waves." 京都大学 (Kyoto University), 2003. http://hdl.handle.net/2433/148529.

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24

Brilla, Pavol. "Realizace zařízení pro měření rozptylu elektromagnetického záření ve struktuře solárních článků." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229105.

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The master thesis discusses the principles, design and realization of the original device for measuring of the electromagnetic radiation scattering in the structure of solar cells. It follows the results of a previous project "Analýza optických vlastností solárných článku" (ev.n.FT-TA3/142) and as well as knowledge gained from Ing. Vladimir Grundling’s master thesis, which has been done under this project. The subject of this thesis was to make a device for measuring of the electromagnetic radiation scattering in the visible spectrum. The aim of this work is an innovation of the previous device, so that the electromagnetic radiation scattering in the near infrared spectrum can be studied. This makes the possibility to qualify the influence of the rear surface of an active part of solar cell on electromagnetic radiation scattering, i.e., on the conversion efficiency of solar energy into electric. For this reasons it was necessary to modify the device, so that we can change the radiation source and detector because of the transparency of silicon wafers for the near infrared area. The work is supported by the project „Barevné solární články s vysokou účinností pro architektonické aplikace“ (FRTI1/168) in cooperation with Solartec s.r.o.

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25

Rodriguez, Raul D., Evgeniya Sheremet, Tanja Deckert-Gaudig, et al. "Surface- and tip-enhanced Raman spectroscopy reveals spin-waves in iron oxide nanoparticles." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-168045.

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Nanomaterials have the remarkable characteristic of displaying physical properties different from their bulk counterparts. An additional degree of complexity and functionality arises when oxide nanoparticles interact with metallic nanostructures. In this context the Raman spectra due to plasmonic enhancement of iron oxide nanocrystals are here reported showing the activation of spin-waves. Iron oxide nanoparticles on gold and silver tips are found to display a band around 1584 cm−1 attributed to a spin-wave magnon mode. This magnon mode is not observed for nanoparticles deposited on silicon (111) or on glass substrates. Metal–nanoparticle interaction and the strongly localized electromagnetic field contribute to the appearance of this mode. The localized excitation that generates this mode is confirmed by tip-enhanced Raman spectroscopy (TERS). The appearance of the spin-waves only when the TERS tip is in close proximity to a nanocrystal edge suggests that the coupling of a localized plasmon with spin-waves arises due to broken symmetry at the nanoparticle border and the additional electric field confinement. Beyond phonon confinement effects previously reported in similar systems, this work offers significant insights on the plasmon-assisted generation and detection of spin-waves optically induced<br>Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich

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26

Xie, Zhongqiang. "Fourth-order finite difference methods for the time-domain Maxwell equations with applications to scattering by rough surfaces and interfaces." Thesis, Coventry University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369842.

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27

Lertwiriyaprapa, Titipong. "An approximate UTD development for the radiation by antennas near or on thin material coated metallic wedges." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1196281470.

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28

Hatziioannou, John. "The scattering of electromagnetic waves by rough surfaces." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627099.

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29

Vishal, Kumar. "Nonreciprocal magnetostatic surface wave in thin ferromagnetic film." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1472018768.

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30

Ben, Khadra Slahedine. "Etude de la signature EM bistatique d'une surface maritime hétérogène avec prise en compte des phénomènes hydrodynamiques." Thesis, Brest, 2012. http://www.theses.fr/2012BRES0089/document.

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Le travail réalisé dans cette thèse s'intègre globalement dans le cadre de I'observation et la surveillance maritime.Afin d'améliorer la reconnaissance et I'identification automatique de cibles noyées dans un environnement perturbé, nous avons opté à la fusion de différentes connaissances et informations concernant une scène observée à distance par des capteurs micro-ondes. En effet, plusieurs phénomènes physiques co-existent et perturbent la propagation des ondes électromagnétiques au-dessus d'une surface et notamment au-dessus d'une surface maritime hétérogène (la réfraction due aux gradients d'indice, la rugosité de la surface de mer, les effets hydrodynamiques non linéaires du type vagues déferlantes, la présence d'objets, les polluants, sillage de navires, zones côtières, ...). Dans ce contexte, le travail présenté dans cette thèse porte sur l'étude de la signature électromagnétique (coefficients de diffusion) d'une surface maritime hétérogène avec la prise en compte des phénomènes hydrodynamiques (linéaires : vagues de capillarité et de gravité, non linéaires : vagues déferlantes). Cette estimation de la signature électromagnétique est effectuée en configuration bistatique (monostatique et propagation avant) et en bande X. L'étude complète de cette problématique est difficile. En effet, le déferlement est un processus dissipatif de l'énergie qui correspond à la dernière étape de la vie d'une vague et qui a donc le plus souvent lieu à I'approche du rivage. Ce phénomène non linéaire produit un pic de mer qui est une augmentation rapide des coefficients de diffusion et qui peut dépasser 10 dB dans une période de 100 ms. Ce pic peut conduire à des échos parasites, qui peuvent être identifiés comme des cibles virtuelles, et par la suite elles peuvent perturber le système de détection radar (fausses alarmes). Par conséquent, pour améliorer le processus de détection et pour réduire le taux de fausses alarmes, il est important de distinguer entre les cibles et les pics de mer générés par des vagues déferlantes. Ceci constitue I’une des motivations et aussi I'intérêt d'étudier la signature électromagnétique des vagues déferlantes dans différentes configurations d'observation de sorte que nous puissions facilement indiquer la présence voir I'identification des pics de mer. Pour contribuer à cette problématique, nous avons proposé une méthodologie basée sur un modèle électromagnétique hybride basé sur une combinaison d'une part de méthodes asymptotiques(SPMI utilisée dans le cadre de ce travail) pour simuler la réponse radar des vagues linéaire (vagues de capillarité et de gravité décrites via le spectre de mer d'Elfouhaily), et d'autre part de méthodes exactes (MoM, FB < Forward-Backward ) retenue dans le travail présenté dans ce manuscrit) pour calculer la réponse électromagnétique des vagues non-linéaires (profils considérés sont issus des résultats du code LONGTANK). Afìn de compléter l'étude théorique et les simulations réalisées, nous avons effectué une phase d'évaluation et de validation par des mesures de signature radar réalisées dans la chambre anéchoïque de I'Ensta Bretagne<br>The work done in this thesis fits generally under the observation and maritime surveillance. To improve the detection and automatic identification of targets embedded in a noisy environment targets, we opted for the fusion of different knowledge and information regarding a remotely observed scene by microwave sensors. Indeed, several physical phenomena co-exist and interfere with the propagation of electromagnetic waves over a heterogeneous sea surface (the refraction due to the index gradients, the roughness of the sea surface, nonlinear hydrodynamic effects like waves breaking, the presence of objects, pollutants, ship wake, coastal areas,..). In this context, the work presented in this thesis focuses on the study of electromagnetic signature (diffusion coefficients) of a heterogeneous sea surface with consideration of hydrodynamic phenomena (linear: capillary and gravity waves, nonlinear: breaking waves). The electromagnetic signature is performed in bistatic configuration (monostatic and forward propagating) and in X-band. The complete study of this problem is difficult.Indeed, the breaking wave is a dissipative process of energy that corresponds to the last stage of the life of a wave and therefore has most often held in the shore. This nonlinear phenomenon produces a sea peak which is a rapid increase of the diffusion coefficients and can exceed l0 dB in a 100 ms period. This peak can lead to clutter, which can be identified as virtual targets, and then they can disrupt the detection radar system (false alarms). Therefore, to improve the detection process and reduce the false alarm rate, it is important to distinguish between targets and sea peaks generated by breaking waves. This represents one of the motivations and also the interest to study the electromagnetic signature of breaking waves in different observation configurations so that we can easily detect and identify the sea peaks. To solve this problem, we proposed a methodology based on a hybrid electromagnetic model which is on a combination of asymptotic methods (SPMI used in this work) to simulate the radar response of linear waves (capillary and gravity waves described via the Elfouhaily sea spectrum) and an exact methods, the method of moment (the FB "Forward-Backward" method is used in this work), to calculate the electromagnetic response of nonlinear waves (profiles are produced by the LONGTANK code). To complement the theoretical study and simulations, we carried out an evaluation and validation phase by measuring the radar signature of breaking wave profiles in the ENSTA Bretagne anechoic chamber

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31

Go, Han Suk. "The design of broadband radar absorbing surfaces." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA240521.

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Thesis (M.S. in System Engineering in Electronic Warfare)--Naval Postgraduate School, September 1990.<br>Thesis Advisor(s): Atwater, H.A. Second Reader: Janaswamy, R. "September 1990." Description based on title screen as viewed on December 29, 2009. DTIC Identifier(s): Radar absorbing materials, radar cross sections, radiation absorbers, lossy dielectrics. Author(s) subject terms: Wave absorber, dielectric material. Includes bibliographical references (p. 55-56). Also available in print.

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32

Kipp, Robert. "Mixed potential integral equation solutions for layered media structures : high frequency interconnects and frequency selective surfaces /." Thesis, Connect to this title online; UW restricted, 1993. http://hdl.handle.net/1773/5974.

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33

Brennan, E. P. "Electromagnetic wave propagation control using LC anisotropic surfaces." Thesis, Queen's University Belfast, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431461.

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34

Lam, Chi Ming. "Theoretical and numerical studies of electromagnetic wave scattering from random media with random rough surfaces and discrete particles /." Thesis, Connect to this title online; UW restricted, 1992. http://hdl.handle.net/1773/5982.

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35

Chen, Jei Shuan. "Wave scattering from very rough surfaces and a study of backscattering enhancement /." Thesis, Connect to this title online; UW restricted, 1990. http://hdl.handle.net/1773/6051.

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36

Tremain, Benjamin James. "The microwave response of metasurfaces." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/24304.

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The aim of this thesis is to investigate surface waves supported on a variety of metallic metasurfaces at microwave frequencies. The goal is to characterise the propagation of these surface waves in the plane of the structure and in some cases study how their presence gives rise to features in the scattering parameters of radiation incident on the metasurface.

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37

Archambault, Alexandre. "Optique des ondes de surface : super-résolution et interaction matière-rayonnement." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00678073.

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Il existe au niveau d'interfaces séparant des milieux de constantes diélectriques de signes opposés des ondes électromagnétiques confinées à proximité de ces interfaces. On parle d'ondes de surface. C'est notamment le cas des métaux et des cristaux polaires : on parle alors de plasmons-polaritons de surface et de phonons-polaritons de surface respectivement. L'objectif de cette thèse est de revisiter certains aspects théoriques associés à ces ondes de surface.Dans un premier temps, en nous basant sur le formalisme de Green, nous donnons un moyen d'obtenir une expression du champ des ondes de surface sous forme de somme de modes. En présence de pertes, ces ondes ont nécessairement un vecteur d'onde ou une pulsation complexe. Nous donnons ainsi deux expressions de leur champ, correspondant à chacun de ces deux cas, et discutons de l'opportunité d'utiliser l'une ou l'autre de ces expressions.Nous posons par la suite les bases d'une optique de Fourier et d'une optique géométrique des ondes de surface. Nous montrons comment obtenir une équation de Helmholtz à deux dimensions pour les ondes de surface, un principe d'Huygens-Fresnel pour les ondes de surface, ainsi qu'une équation eikonale pour les ondes de surface, qui s'applique sous certaines hypothèses. Nous nous intéressons également à la superlentille proposée par Pendry, qui s'appuie sur les ondes de surface. Nous étudions notamment le fonctionnement de cette superlentille en régime impulsionnel, et montrons qu'en présence de pertes, il est possible d'obtenir une meilleure résolution avec certaines formes d'impulsion par rapport au régime harmonique, au prix d'une importante baisse de signal toutefois.Nous développons ensuite un traitement quantique des ondes de surface. Nous calculons au préalable une expression de leur énergie, et nous donnons une expression de leur hamiltonien et de leurs opérateurs champ. Sans pertes, nous montrons que le facteur de Purcell prédit par notre théorie quantique est rigoureusement égal au facteur de Purcell calculé avec des outils classiques. Nous comparons ensuite ce facteur de Purcell à celui calculé classiquement avec pertes, et montrons sur un exemple que les pertes peuvent être négligées dans de nombreux cas. Nous donnons enfin une expression des coefficients d'Einstein associés aux ondes de surface permettant d'étudier la dynamique de l'inversion de population d'un milieu fournissant un gain aux ondes de surface. Nous appliquons par la suite ce formalisme quantique à l'interaction électrons-phonons-polaritons de surface dans les puits quantiques, notamment leur interaction avec un mode de phonon du puits particulièrement confiné grâce à un effet de constante diélectrique proche de zéro (epsilon near zero, ENZ).

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38

Lockyear, Matthew John. "Electromagnetic surface wave mediated absorption and transmission of radiation at microwave frequencies." Thesis, University of Exeter, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410814.

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39

Li, Kevin. "Electromagnetic wave scattering by surface discontinuities in a perfectly conducting ground plane." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/14036.

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40

Wang, Shiyi. "Engineering Electromagnetic Wave Properties Using Subwavelength Antennas Structures." University of Dayton / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1427837723.

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41

Alshannaq, Shadi Sami. "Nonreciprocal Millimeter and Sub-Millimeter Wave Devices Based on Semiconductor Magnetoplasma." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313134612.

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42

Wijesundara, Shanka N. "Studies of Electromagnetic Backscattering from Ocean Surfaces." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1565976614784442.

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43

Cetnar, John. "Full Wave Electromagnetic Simulations of Terahertz Wire Grid Polarizers and Infrared Plasmonic Wire Gratings." Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1398356024.

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44

Swatek, David R. "Investigation of single-source surface integral equations for electromagnetic wave scattering by dielectric bodies." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0016/NQ45140.pdf.

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45

GALAL, TAREK. "Interactions ondes electromagnetiques et surfaces rugueuses : applications a la surface cutanee." Besançon, 1989. http://www.theses.fr/1989BESA2007.

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Solution analytique de la dispersion d'une onde electromagnetique par une surface rugueuse, prenant en compte les parametres locaux de la topographie=une autre technique est developpee basee sur l'utilisation d'elements finis ou de differences finies

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46

Wilson, Glenn Andrew, and glenn wilson@griffith edu au. "Plane Wave Propagation Problems in Electrically Anisotropic and Inhomogeneous Media with Geophysical Applications." Griffith University. School of Microelectronic Engineering, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030325.210206.

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Boundary value problems required for modelling plane wave propagation in electrically anisotropic and inhomogeneous media relevant to the surface impedance methods in electromagnetic geophysics are formally posed and treated. For a homogeneous TM-type wave propagating in a half space with both vertical and horizontal inhomogeneities where the TM-type wave is aligned with one of the elements of the conductivity tensor, it is shown using exact solutions that the shearing term in the homogeneous Helmholtz equation for inclined anisotropic media: [Equation 1], unequivocally vanishes and solutions need only be sought to the homogeneous Helmholtz equation for biaxial media: [Equation 2]. This implies that those problems posed with an inclined uniaxial conductivity tensor can be identically stated with a fundamental biaxial conductivity tensor, provided that the conductivity values are the reciprocal of the diagonal terms from the Euler rotated resistivity tensor: [Equation 3], [Equation 4], [Equation 5]. The applications of this consequence for numerical methods of solving arbitrary two-dimensional problems for a homogeneous TM-type wave is that they need only to approximate the homogeneous Helmholtz equation and neglect the corresponding shearing term. The self-consistent impedance method, a two-dimensional finite-difference approximation based on a network analogy, is demonstrated to accurately solve for problems with inclined uniaxial anisotropy using the fundamental biaxial anisotropy equivalence. The problem of a homogeneous plane wave at skew incidence upon an inclined anisotropic half space is then formally treated. In the half space, both TM- and TE-type waves are coupled and the linearly polarised incident TM- and TE-type waves reflect TE- and TM-type components. Equations for all elements of the impedance tensor are derived for both TM- and TE-type incidence. This offers potential as a method of predicting the direction of anisotropic strike from tensor impedance measurements in sedimentary environments.

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47

Browe, Bryan Everett. "Wave Scattering from Structures that Display Areas of Small Radii of Curvature in the Presence of an Extended Planar Surface." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/9746.

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In many applications, it is necessary to simulate wave scattering from surfaces that have small radii of curvature relative to the incident wavelength. Surface features smaller than an electromagnetic wavelength are known to create diffracted fields over a wide range of scattering angles. In this thesis, the significance of such effects at low grazing angles with the presence of an extended planar surface is considered. The magnetic field integral equation (MFIE) describing the currents on such surfaces is used to solve for the bistatic scattered fields. The integral equations are discretized using the moment method and solved using the Method of Ordered Multiple Interactions (MOMI) iterative procedure. This thesis will concentrate on normal incidence and low grazing angle (LGA) incidence, specifically an incident angle of 80 degrees. The surface used in the analysis is a one-dimensional, perfectly-conducting wedge-on-a-plane with a varying radius of curvature at the wedge tip and Gaussian tails that smoothly extend the wedge to the plane surface. This surface displays continuous first and second derivatives over the entire surface. The radius of curvature at the wedge tip is varied between 0.0125 wavelengths and 8 wavelengths. The form of the bistatic scattered fields will be investigated for three different wedge height to wedge width geometries. The surface scattering mechanisms and their respective location and form in the scattered field will be discussed. The dependence of the scattered field pattern on the radius of curvature at the wedge tip and the beam width of the incident field will be considered. The difficulties associated with using a numerical technique on extended surfaces where a significant source of diffracted energy is present will also be examined. This includes the issue of sampling a surface that contains areas of small radii of curvature and the issue of surface truncation when significant currents due to tip diffraction are produced well outside the illuminated area. Both TE (VV) and TM (HH) polarization will be considered. This thesis also analyzes the scattered fields for a perfect electric conducting (PEC) ridge and well in the presence of an extended planar surface for an incident angle of 70 degrees. The dual-surface magnetic field integral equation (DMFIE) formulation for a one-dimensional extended surface will be used to solve for the unknown currents on the surface of the scatterer. The DMFIE formulation leads to a second kind integral equation that can be solved via the MOMI series with the proper choice of the parameters appearing in the DMFIE formulation. The bistatic scattered fields for several ridge and well geometries are examined for both TE and TM polarization.<br>Master of Science

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48

Dean, Cayla Whitney. "Turbulent and Electromagnetic Signature of Small- and Fine-scale Biological and Oceanographic Processes." Diss., NSUWorks, 2018. https://nsuworks.nova.edu/occ_stuetd/492.

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Small- and fine-scale biological and oceanographic processes may have a measurable electromagnetic signature. These types of processes inherently involve turbulence and three-dimensional dynamics. Traditional models of the electromagnetic signature of oceanographic processes are of an analytical nature, do not account for three-dimensional boundary layer dynamics or turbulence, self-inductance, and may not describe the variety of the environmental conditions occurring in the ocean. In order to address this problem, I have implemented magnetohydrodynamic (MHD) computational fluid dynamics (CFD) tools, which has allowed for the evaluation of the electromagnetic signature of a number of small- and fine-scale biological and oceanographic processes in the ocean. The suite of computational tools has included the commercial models ANSYS Fluent, coupled with the MHD module, and ANSYS Maxwell. These computational tools have been well-established in fluid and electromagnetic engineering. The application of CFD and MHD tools in oceanography is new but is undergoing rapid development. In this work, substantial effort was made toward the CFD, MHD, and magnetostatic model verification and identification of model limitations. Verifications of the CFD, MHD, and magnetostatic models were conducted by successfully comparing their results with the field measurements and laboratory experiments. Comparison with the traditional (analytical) models for surface and internal waves, has revealed their limitations related to bottom boundary layer physics, effect of self-inductance, and, to a lesser extent, the magnetic permeability difference at the air-sea interface. These limitations become important for shallow water internal waves. As a result, the traditional models significantly overestimate the magnetic signature of internal waves observed at the Electromagnetic Observatory. After model verification with the field and laboratory data, the computational models were then applied to evaluate the magnetic signature of diel vertical migration (DVM) of zooplankton, surface waves, internal wave solitons, freshwater lens spreading, and Langmuir circulation. The quantitative estimates have been made for typical environmental conditions. In other environmental conditions, their magnetic signature may be somewhat different. The suite of computational models developed in this dissertation work allows for the estimation of the magnetic signature of fine- and small-scale oceanographic processes in virtually any environmental conditions (e.g., in oil emulsions). I anticipate the result of this study will have Naval, environmental, and oil exploration applications.

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Lu, Donghang [Verfasser], Rolf [Akademischer Betreuer] Jakoby, and Mario [Akademischer Betreuer] Kupnik. "Dual-load Hybrid Detection of Water Content Using Electromagnetic and Surface Acoustic Wave Sensors / Donghang Lu ; Rolf Jakoby, Mario Kupnik." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2016. http://d-nb.info/1121206972/34.

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50

Boubakra, Abdelkrim. "Etude de la propagation d'une onde electromagnetique de surface de type he : :(11) en hyperfrequence." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF21033.

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On etudie en hyperfrequence d'un point de vue analytique, numerique et experimental, la propagation d'une onde electromagnetique de type he::(11) a la surface d'un conducteur cylindrique gaine d'une couche dielectrique, un deuxieme dielectrique occupant le reste de l'espace

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