To see the other types of publications on this topic, follow the link: Dielectric waveguide.
Dissertations / Theses on the topic 'Dielectric waveguide'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Dielectric waveguide.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Barkley, Edward R. (Edward Robert). "The integration of InP /InGaAsP ridge waveguide structures with dielectric waveguides on silicon." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/38682.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2007.Includes bibliographical references (p. 261-271).
Chip-to-chip optical interconnect technology, which is being explored as a potential replacement for copper chip-to-chip interconnects at data transmission rates exceeding 10 Gb/s, is one of several technologies that could be enabled by the monolithic integration of III-V optoelectronic devices on a silicon integrated circuit. Two significant capabilities required to achieve this monolithic integration were addressed: the assembly of III-V device structures on silicon and the fabrication of the waveguides that perform the intra-chip routing of the optical signal to and from these integrated device structures. These waveguides, consisting of a silicon oxynitride core (n = 1.6) and a silicon dioxide cladding (n = 1.45) were deposited via plasma-enhanced chemical vapor deposition (PECVD). The integrated InP/InGaAsP structures were fabricated using an existing novel technique for preparing very thin (on the order of 5 pm thick) substrate free rectangular structures (approximately 145 pm wide by 300 pm long) with cleaved facets. Using a pick-and-place method, the InP/InGaAsP structures were assembled in 6 pm deep rectangular wells formed by etching through the waveguide stack. The resulting configuration of the integrated devices in the wells facilitated end-fire coupling with the silicon oxynitride waveguides.
(cont.) Transmission spectrum measurements for this configuration verified the desired end-fire optical coupling through the integrated InP/InGaAsP device structures with a total coupling loss of 17.75 dB. This loss was shown through measurements and finite difference time domain (FDTD) simulations to be a function of integrated device misalignment, silicon oxynitride waveguide design, length of the gaps between the etched well edges and the device facets, and the well etch properties. Based on FDTD simulations and device misalignment statistics, it was shown that realistic, feasible improvements in the device alignment coupled with the use of higher index contrast waveguides could lower the coupling loss to 3.25 dB.
by Edward R. Barkley.
Ph.D.
2
Kot, J. S. "Rectangular dielectric waveguide for millimetre wave components." Thesis, University of Bath, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374605.
Full text
3
Clark, Jeffrey. "Double Negative Metamaterials in Dielectric Waveguide Configurations." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/28708.
Full textAbstract:
With the recent resurgence of interest in double negative (DNG) materials and the reported construction of a metamaterial with DNG characteristics, applications of these materials become feasible and examination of the behavior of systems and devices a potentially fruitful topic. The most promising area of research, upon inquiry into past work related to DNG materials, proves to be dielectric waveguides. The present investigation, then, focuses on the inclusion of DNG materials in various planar dielectric waveguide configurations. These waveguides involve a core region surrounded by various numbers of symmetrically-placed cladding layers.
The present investigation involves the review of the electromagnetic properties of DNG materials by a thorough analysis based on Maxwell's equations. The use of a negative index of refraction for these materials is justified. These results are then used to perform a frequency domain analysis of an N-layer formulation for dielectric waveguides which is general for any combination of DNG and double positive (DPS) materials. This N-layer formulation allows for the derivation of the characteristic equation, which relates the operating frequency and the propagation constant solutions, along with the cutoff conditions and field distributions. A causal material model which obeys the Kramers-Kronig relations and which is based on measurements of a realized metamaterial is studied and used in the investigation in order to produce realistic results.
The N-layer formulation is then applied to the three-layer (slab) waveguide and known results are reviewed. A new interpretation of intramodal degeneracy is given, whereby degenerate modes are split into two separate modes, one with positive phase velocity and one with negative phase velocity but both with a causal positive group (energy) velocity. Next, the formulation is applied to the five-layer waveguide. New behaviors are observed in this case which are not seen for the three-layer waveguide, including the return of the fundamental mode in some cases, whereas it is never present for the three-layer guide, the absence of certain higher-order modes in some situations and the appearance of new modes. Additionally, for some configurations the order of the even and odd modes in the DNG frequency range is found to be reversed from that of conventional waveguides.
The photonic crystal waveguide, which involves an infinite number of periodically placed cladding layers, is next studied using ray analysis, and a slight variation of the N-layer formulation is used to compare these results with those of the pseudo-photonic crystal waveguide. The pseudo-photonic crystal waveguide is identical to the photonic crystal waveguide with the exception that it has only large but finite number of layers. It is seen that the results of these two cases are similar for conventional modes, but the photonic crystal waveguide allows for new modes called photonic crystal modes which are inaccessible through conventional waveguides. Interesting phenomena such as mode crossings among the photonic crystal modes are observed and discussed.
Using the results from the frequency domain analysis of the five-layer waveguide, a Fourier transform technique is used to study pulse propagation in a waveguide containing DNG materials. A Gaussian pulse is launched in the waveguide over the frequency range covering a portion of the positive- and negative-phase-velocity fundamental transverse electric (TE) modes. Splitting of the input pulse into two separate pulses is observed, where both of these new pulses have a causal, positive energy velocity. The interpretation of intramodal degeneracy given in previous discussions is buttressed with evidence from this portion of the investigation, thus completing the analysis and bringing the present study to its conclusion.Ph. D.
4
Aryal, Krishna Prasad. "Design and simulation of a hybrid dielectric waveguide." Thesis, University of Massachusetts Boston, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1599234.
Full textAbstract:
Waveguides, in general are used as a means to route photons. Traditional dielectric waveguides, composed of a high index core surrounded by a low index cladding, produce maximum field intensities far from dielectric interfaces. This thesis presents the design of a plasmonic enhanced waveguide, which relocates the maximum optical field intensity from the center of the waveguide to an interfacial region defined by a dielectric and a negative index material. This is accomplished through the use of a metal film, positioned on top of a traditional ridge waveguide in those places where one wishes to excite a plasmon mode as opposed to the more traditional dielectric mode. Plasmon modes have their highest field intensity at the interface located between the metal and the dielectric. In this thesis, the waveguide dimensions of a hybrid dielectric waveguide are determined with the intent of producing single mode operation for a ridge waveguide with and without metal on top. A commercial Eigen mode solver (MODE Lumerical) is used to obtain all field profiles, waveguide effective index and waveguide loss. Multiple simulations were used to design a waveguide, which supports a single plasmonic mode when the metal film is in place and a single dielectric mode when the metal film is absent. Such a waveguide is expected to find use in the field of integrated quantum optics where quantum dots, defined by near surface confining potentials, require high interfacial fields for maximum dot/field interactions. Further, based on the final waveguide design height of ( 5µm ) and width of ( 7.9µm ), an effective index of ( 3.687 ) results when operated in the plasmon mode and (3.619) when operated in dielectric mode. This change in refractive index suggests such hybrid dielectric/plasmon waveguides can be used for the design of Bragg reflectors leading to plasmonic cavities, which, when coupled to the proposed near surface located quantum dots, can be used for the production and detection of single photons, required by many diverse engineered quantum systems, such as quantum communication, quantum metrology and quantum computation.
5
Abbas, Zulkifly. "Determination of the dielectric properties of materials at microwave frequencies using rectangular dielectric waveguide." Thesis, University of Leeds, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569541.
Full text
6
Karadeniz, Erol. "Cylindrical high index contrast thin film dielectric optical waveguide." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2005. http://wwwlib.umi.com/cr/syr/main.
Full text
7
Van, Gassen Kwinten. "Application of Twist Symmetry to a Cylindrical Dielectric Waveguide." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-286829.
Full textAbstract:
The application of higher order symmetry to waveguide design is an active field and is showing evidence of improvement over traditional waveguide designs. There are two forms of higher symmetry: glide symmetry and twist symmetry. Glide and twist symmetry have previously been applied to bounded waveguide, and a recent work applied glide symmetry to the design of a dielectric slab waveguide. This work is the first application of twist symmetry to the design of a dielectric waveguide. In this work a twist symmetric dielectric rod waveguide was designed and simulated using the eigenmode, truncated structure and multimode method. The twist symmetric dielectric rod waveguide is demonstrated to have stopbands, analogous to those demonstrated in metal waveguides based on glide symmetry. In addition the waveguide also shows circular polarization based birefringence and circular polarization based stopbands. A novel unit cell was created which demonstrates the phenomenology of dielectric twist symmetry in the X-band. The dispersion diagram of this structure is calculated using the eigenmode and multimode method and the S-parameters of the novel waveguide were calculated using the truncated structure method. There is strong agreement in the propagation and attenuation characteristics from all three computational methods. The novel unit cell has potential applications as an inline polarization based filter for the fundamental HE11 mode of dielectric rod waveguides. With potential applications to communication and sensing systems.Användandet av högre symmetrier I vågledardesigner är ett aktivt forskningsfält och fördelar över traditionell vågledardesign har påvisats. Det finns två typer av högre symmetri: glid- och vridsymmetri. Glid- och vridsymmetri har tidigare applicerats på stängda vågledare och glidsymmetri har nyligen applicerats på en dielektrisk vågledare. I detta arbete appliceras vridsymmetri i designen av en dielektrisk vågledare för första gången. I det här arbetet designas och simuleras en vridsymmetrisk dielektrisk med hjälp av egenmods, trunkerad-struktur- och mutimods-metoderna. Den vridsymmetriska dielektriska vågledaren påvisar stoppband, liknande de som tidigare visats i glidsymmetriska strukturer. Vidare visar strukturen cirkulärpolariserad dubbelbrytning och olika stoppband för de två cirkulära polarisationerna. En ny enhetscell togs fram vilken påvisade fenomenen kopplade till dielektrisk vridsymmetri för X-bands frekvenser. Dispersionsdiagrammet för strukturen beräknades med hjälp av egenmods- och multimodsmetoderna, och S-parametrarna för vågledaren beräknades med en trunkerad struktur. Resultaten från de olika metoderna stämmer väl överens gällande propagering och försvagning. Enhetscellen finner användning som polarisationsfilter för den fundamentale HE11-moden av dielektriska cirkulära vågledare och kan appliceras i kommunikations- och avkänningssystem.
8
Wells, Colin G. "Analysis of shielded rectangular dielectric rod waveguide using mode matching." University of Southern Queensland, Faculty of Engineering and Surveying, 2005. http://eprints.usq.edu.au/archive/00001524/.
Full textAbstract:
The limit of current technology for mobile base station filters is the multimode filter, in which each cavity supports two (or possibly three) independent degenerate resonances. Shielded dielectric resonators with a rectangular cross-section are useful in this application. In the design of these filters, manufacturers are using software packages employing finite element or finite difference time domain techniques. However, for sufficient accuracy these procedures require large numbers of points or elements and can be very time consuming. Over the last decade research using the mode matching technique has been used to solve this kind of difficulty for various types of filter design and waveguide problems. In this thesis a mode matching method and computer program is developed to calculate the propagation coefficients and field patterns of the modes in a shielded rectangular dielectric rod waveguide. Propagating, complex, evanescent and backward wave modes are included and the work shows the presence of a dominant mode, and other fundamental modes, not previously identified. The effect of the shield proximity on the propagation characteristics and mode spectrum is investigated, together with the limitations on the accuracy of the mode matching method. In addition, the fields within the shielded rectangular dielectric rod waveguide, are used to calculate the attenuation coefficient of the dominant and fundamental modes. The influence on the attenuation coefficient of the proximity of the shield to the rod is also evaluated for these modes and limitations on accuracy are discussed. The calculated numerical results for the propagation and attenuation coefficient values are verified by measurement. The propagation coefficients results are typically within 2% of those measured. Verification of the attenuation coefficient results is achieved by comparing calculated and measured Q at the resonant frequencies of a number of shielded rectangular dielectric rod resonators. The difference between calculated and measured Q values is on average less than 4%. In the absence of a full solution of the shielded rectangular dielectric rod resonator, these results provide useful design information for this structure. In addition, the work reported in this thesis provides a basis for a full electromagnetic solution of this type of resonator. This would encompass the cubic dielectric resonator in a cubical cavity.
9
Boese, Ingo. "Millimetre wave measurements and device characterisation at 140 GHz." Thesis, University of Kent, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242860.
Full text
10
Ogunlade, Olumide. "Measurement of the microwave dielectric properties of liquids using waveguide structures." Thesis, University of Leeds, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556018.
Full textAbstract:
A variety of waveguide structures have been analysed for the measurement of the complex dielectric permittivity of liquids. Mode matching techniques are im- plemented to solve the forward problem of computing the scattering parameters for a sample of known permittivity filling a rectangular metal waveguide. Three different sample geometries are used. In the first, the liquid and the sample holder completely fill the waveguide cross section. As a result, only the dominant waveguide modes are matched across the discontinuity interface and an exact an- alytical relation between the S parameters and permittivity can be written. The second and third configurations are concentric cylinders and rectangles respec- tively, partially filling a metal waveguide, hence higher order modes are taken into account in the formulation. For the partially filled rectangular sample, a generalised scattering matrix method to obtain the overall scattering parameters due to the several discontinuity regions. Iterative methods are then introduced to solve the inverse problem of recover- ing the unknown permittivity from simulated or measured scattering parameters. For the partially filled waveguides, because an exact analytical relation does not exist, objective( error) functions are defined and minimized. The partially filled rectangular sample case is extended to obtain the resonant frequency and qual- ity factor of a dielectric loaded resonant cavity, and the results compared to the approximation normally used for the cavity perturbation technique. Finally, a rectangular dielectric waveguide method for liquid measurements was developed. This method has a treatment similar to the well known free space tech- niques. It has a distinct advantage of relaxing the strict requirements of sample dimension associated with metal waveguides, especially at higher frequencies.
11
Miller, Gregory A. "A circuit model for two-path cutoff waveguide dielectric resonator filters." Thesis, Monterey, Calif. : Naval Postgraduate School, 1992. http://handle.dtic.mil/100.2/ADA247785.
Full textAbstract:
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, March 1992.Thesis Advisor: Knorr, Jeffrey B. "March 1992." Includes bibliographical references (p. 58-59). Also available in print.
12
Beltran, Madrigal Josslyn. "Integration of a single photon source on a planar dielectric waveguide." Thesis, Troyes, 2017. http://www.theses.fr/2017TROY0007/document.
Full textAbstract:
Le développement de dispositifs optiques intégrés dans des domaines tels que l'information quantique et la détection de molécules est actuellement dirigé vers l'intégration de nanosources (NS) sur des systèmes sur puce avec faible pertes de propagation. Cette thèse montre une contribution à la conception, à la fabrication et à la caractérisation de structures photonique-plasmoniques en vue de l'intégration d'une seule NS sur des puces optiques à travers le spectre visible. Nous recherchons à optimiser l’efficacité d’excitation et de collection de l'émission de la fluorescence d'une NS en combinant un nano-prisme en or et une structure formée par une couche de dioxyde de titane (TiO2) et un guide d'ondes à échange d'ions (IEW) sur verre. Le couplage entre les modes permet un transfert efficace de l'énergie entre un mode faiblement confiné dans l'IEW vers un mode plasmonique confiné dans un volume effectif de quelques nanomètres cubes. Ce mode confiné interagit avec une NS en améliorant son émission de fluorescence par l'effet de facteur Purcell. En utilisant le théorème de réciprocité de l'électromagnétisme, nous avons étudié le cas réciproque où la lumière émise par la NS peut être collectée dans les modes photoniques du IEW.La caractérisation a été réalisée en champ lointain et en champ proche avec en particulier l'utilisation d'un microscope optique de champ proche à sonde diffusante (SNOM). Nous avons proposé une configuration SNOM qui permet d'imiter l'interaction d'une NS et des systèmes guidés, cartographiant la densité locale des modes guidés (LDOM)The development of integrated optical devices in areas such as quantum information and molecular sensing is currently directed towards the integration of nanosources (NS) into systems on a chip with low propagation losses. This thesis shows a contribution on the design, fabrication, and characterization of photonic-plasmonic structures towards the integration of a NS on optical chips across the visible spectrum. We pursue the efficient excitation and collection of the fluorescence emission of a NS by making use of the interaction between an electromagnetic field concentrator (gold nanoprism) and an integrated optics structure formed by a high-index layer of titanium dioxide (TiO2) and a low-contrast index ion exchanged waveguide on glass (IEW). The coupling mode allows an efficient transfer of the energy between a weakly confined mode in the IEW and a plasmonic mode confined in an effective volume of few cubic nanometers. This confined mode interacts with a NS enhancing its florescence emission through Purcell factor effect. Using the reciprocity theorem of electromagnetism, we studied the reciprocal case where the light emitted by the NS can be collected into the photonic modes of the IEW.The characterization was performed in the far and in the near field with the use of a scanning near-field optical microscopy (SNOM). We proposed a SNOM configuration that allows us to imitate the interaction of a NS and guided systems, mapping the local density of guided modes (LDOM)
13
Sewall, Lyle Matthew. "Dielectric Characterization: A 3D EM Simulation Approach." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/35031.
Full textAbstract:
A new approach is presented that relies upon 3D electromagnetic simulation results to characterize the complex permittivity of homogeneous dielectric materials. By modeling the test fixture and obtaining a set of simulated S-parameters through an iterative solution process, the dielectric constant and loss tangent can be found. With further development, the 3D simulation results may be used to replace the need for complex theoretical analysis of the measurement geometry.
The method is applied to an X-band rectangular waveguide setup, for which the theoretical S-parameters can be readily calculated. A Teflon sample, for which the dielectric properties are well-known, is used for all measurements and calculations. After presenting a detailed derivation to obtain the theoretical S-parameters, the Teflon sample is measured and compared to the theoretical results, from which the comparison shows great promise. An inverse solution algorithm is used to solve for the material properties from the experimental S-parameters.
Low-frequency measurement of the Teflon sheet was performed by using a dielectric capacitor test fixture. The results show the effect of an air gap between the electrode and sample, producing serious errors.Master of Science
14
Martínez, Brito Juan. "Characterization of Dielectric Samples at Microwave Frequencies Using Substrate Integrated Waveguide Techniques." Thesis, Universidad de las Américas Puebla, 2010. http://catarina.udlap.mx/u_dl_a/tales/documentos/lmt/martinez_b_j/.
Full textAbstract:
Complex permittivities of the materials are evaluated at microwave frequencies
by using the Substrate Integrated Waveguide (SIW) cavity resonator and Epsilon
Near Zero (ENZ) technology.
Dielectric parameters such as dielectric constant and dielectric loss of
solids samples, solvents and alcohols are determined by measuring the change
in the resonant frequency and in the Q factor, due to the introduction of
the samples in to these resonant structures.
High Frequency Structure Simulator (HFSS) has been used to design and optimize
the resonant structures.
Simulations and measurements are performed with different substrates and
different dielectric samples to validate the cavity perturbation theory using
substrate integrated waveguide (SIW) cavity resonator.
For ENZ structure, simulations are performed with various height ratios to
choose an optimized ratio that allows higher sensitivity.
Simulation and measurement results of cavity resonator and ENZ tunnel are
in good agreement with theoretical values. Both structures present low profile,
low cost, ease of fabrication and ease of integration, which adds important
characteristics for portable material measurement systems.
15
Eshrah, Islam A. "Waveguide and metaguide excitation of dielectric resonator antenna arrays using slots and probes /." Full text available from ProQuest UM Digital Dissertations, 2005. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1267222711&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1184857149&clientId=22256.
Full text
16
Korampally, Venumadhav. "A novel ultra-low refractive index nanoporous dielectric based aqueous core waveguide system." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4878.
Full textAbstract:
Thesis (Ph.D.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on March 10, 2009) Includes bibliographical references.
17
Culver, James William. "The analysis of dielectric loss in co-planar waveguide structures using generalized transverse resonance." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001036.
Full text
18
Purdy, Daniel S. "Modal and radiation characteristics of the crossed-septum dielectric loaded waveguide for wideband applications." Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06062008-155502/.
Full text
19
Cha, Jun Ho. "A steerable array antenna using controllable microwave dielectric slab phase shifters on a coplanar waveguide /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/5824.
Full text
20
Peic, Antun. "Mesoporous thin-film materials studied by optical waveguide spectroscopy." Thesis, University of Bath, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518293.
Full textAbstract:
A method was developed to access the interior of light-guiding structures in order to exploit the enhanced sensing potential of the highly confined electromagnetic field distributions, located within the core of a waveguide. The work presented in this thesis explores therefore the possibilities of optical waveguide spectroscopy utilising transparent mesoporous thin-film waveguides deposited on top of athin gold layer. These multi-layer assemblies are employed in a prism-coupling attenuated total internal reflection (ATR) configuration. The angular read-out of the reflected light intensity allows label-free detection schemes with high sensitivity to changes of the dielectric environment in the case of the presence of analyte molecules within the probing region. This optical waveguide spectroscopy technique has been used to study the real-timediffusion of Ruthenium 535-bisTBA (N-719) dye into mesoporous nanocrystalline titaniumdioxide films. The porous films were prepared on top of gold substrates and prism coupling was used to create a guided wave in the nanocrystalline film. Dying was carried out by bring the film into contact with a 3 x 10-4 moldm-3 dye solution and using optical waveguide spectroscopy to monitor the change in both the refractive index and theextinction coefficient of the nanoporous layer as dye diffused into the porous network. Dyeuptake in a 1.27 μm film was slow with the refractive index of the film still increasing after 22 hours.
21
Sibbald, Christopher L. "A new technique for modeling open-ended waveguide structures and its application to dielectric spectroscopy." Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/7808.
Full textAbstract:
A novel technique for modeling the aperture admittance of open-ended waveguide structures radiating into a homogeneous, lossy dielectric half-space is presented. This technique combines both analytical and numerical approaches to express the aperture admittance as rational function of frequency and the relative permittivity of the external medium. The coefficients of the rational approximation, which depend upon the geometry of the waveguide and aperture, are determined in a very convenient manner from a relatively small number of computed admittances. This computed data is obtained via a full-wave movement method solution and, hence, includes the effects of radiation and energy storage in the near-field and evanescent waveguide modes. The accuracy of the numerical method is demonstrated by comparison with measured values. The new technique is successfully applied to obtain a model for the open-ended coaxial line geometry. The new model has important applications in the field of dielectric spectroscopy. In addition to yielding accurate solutions for the aperture admittance of the line as a function of the permittivity of the external medium, the model yields a unique solution to the inverse problem and permits a rigorous sensitivity and uncertainty analysis.
22
Andriyas, Tushar. "Surface Wave Propagation in a Dielectric Waveguide Loaded with an Anisotropic, Conductive, and Spatially Dispersive Substrate." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/395.
Full textAbstract:
This thesis presents an analytical treatment of surface waves inside a dielectric slab loaded with a conductive and spatially dispersive semiconductor-like substrate. The work is primarily focused on the modelling of the substrate and getting the field solutions out from the Helmholtz equation. Appropriate boundary conditions have been used in order to get a unique dispersion relation. The surface wave modes are then extracted from the relation by using a root-searching algorithm, which in this work is the MATLAB Genetic Algorithm toolbox. Many different substrate configurations have been considered, starting from the very basic isotropic case to the most complex spatial dispersion case. In between, anisotropicity has also been added to the substrate by turning the static magnetic field on. The permittivity tensors are derived from the fluid transport equations and through the course of the thesis, extra terms such as plasma oscillations, damping, cyclotron resonance, and density perturbations are added. Many assumptions, approximations, and limitations of this analytical treatment have also been addressed. Simulations results have been shown to see the effects of these various terms. The substrates analyzed in the chapters are only a theoritical approximation of an actual substrate. The main idea behind this study is to get a feel for how the transport equations can be utilized to obtain properties that might be on a macroscopic scale. The physical significance of this expose has also been discussed in the last chapter. Issues such as scalability to space plasmas and future ramifications are also included. The study done thus far will be useful in investigating such plasma mediums.
23
Skidmore, Scott. "Analysis and Optimization of Broadband Measurement Cells for the Characterization of Dielectric Polymer Films." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4224.
Full textAbstract:
The current techniques and methodologies used in the field of material characterization are well documented and widely accepted as reliable and accurate. However, literature describing these techniques focuses on the algorithms used during material characterization; few studies have reposted on the design of, and the selection criteria for, the test fixtures themselves. This research focuses on the measurement cell with the goal of determining the sensitivity of the measurement cell to the addition of a thin film material.
Microstrip and coplanar waveguide were chosen for the analysis, which included three configurations of each transmission line geometry: a reference with no additional thin film material, one with the thin film on top of the conductors and one with the thin film beneath the conductors but on top of the transmission line substrate. The scattering parameters for the reference cell are compared to the scattering parameters of the test cell with the thin film material. The additional thin film material changes the effective dielectric constant of the reference cell; this change is evident in the phase and amplitude of S21.
The optimum measurement cell is the one that experiences the greatest change to the effective dielectric constant with the addition of the thin film. Thus the greatest difference in S21 between the reference cell and the test cell is indicative of the reference cell's sensitivity. The figure of merit (FOM) to determine the structure's sensitivity is the integration over frequency of the magnitude of the vector difference of S21. The analysis shows that the double-layered CPW measurement cell was the most sensitive.
Once the optimum structure was determined an analysis of the sensitivity of the FOM to changes in the physical and electrical properties of the reference structure was conducted. The most important factors in the selection of the reference cell as evident by the FOM's sensitivity are the substrate to thin film dielectric constant ratio and the CPW conductor aspect ratio to the thin film thickness. In particular, thinner films require a smaller conductor gap while wider gaps are preferable for thicker films.
Measurement of four different CPW geometries, each covered in a 300 micron Polydimethylsiloxane thick film, validate the analysis process. The measurement cells differ in the conductor aspect ratio. The values of the measured FOMs trend as predicted by the simulation analysis.
24
Jost, Matthias [Verfasser]. "Liquid Crystal Mixed Beam-Switching and Beam-Steering Network in Hybrid Metallic and Dielectric Waveguide Technology / Matthias Jost." Aachen : Shaker, 2018. http://d-nb.info/1186590653/34.
Full text
25
Syk, Madeleine, and Joakim Vollmer. "Characterizing particulate carbon using dielectric property measurements." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-346536.
Full textAbstract:
Interest in effects of carbonaceous particles in the atmosphere has recently taken an upswing due to knowledge of how these particles affect our environment. Carbonaceous aerosols are characterized by their dark color, giving them the ability to absorb both incoming and outgoing radiation of all wavelengths in the atmosphere. If these particles are deposited on snow or ice they blacken the surface, with an increased rate of melting as a consequence. These particles play a significant role in climate change and it is important to characterize the particles in order to determine their environmental impact and their origin. In this thesis, two non-destructive dielectric measurement approaches for characterizing carbonaceous particles at microwave frequencies were explored: measurements with an impedance analyzer and measurements using a cavity resonator. Measurements were carried out on quartz filters containing concentrations of carbon normally found in snow in northern Scandinavia. To validate the carbon concentration on the filters a field trip to northern Sweden was conducted. Snow samples were collected and analyzed in regards of carbon content, confirming that the amount of carbon on the filters were accurate. The impedance analyzer showed great uncertainty and the results were not precise enough to determine the credibility of the approach. Measurements with the cavity resonator showed some promising results due to its extreme sensitivity but require adjustments to distinguish different particle types from each other. Thus, it is expected that the use of a cavity resonator operating at microwave frequencies will become an applicable method for characterizing carbonaceous particles in the future.
26
Jeong, Jae Soon. "An evaluation of coplanar line for application in microwave integrated circuitry." Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23213.
Full textAbstract:
Approved for public release; distribution is unlimitedA general study of conductor backed coplanar waveguide is presented. The impedance (Z(0)) and effective dielectric constant (ɛ(reff)) of conductor-backed coplanar waveguide (CBCPW) have been calculated by using a variational method and the boundary point matching method. In this present work only the TEM dominant low frequency propagation mode of coplanar line has been considered. Experimental facilities are vector network analyzer (HP8409) and bench-instrument measurements.
http://archive.org/details/evaluationofcopl00jeon
Captain, Korean Air Force
27
Рыбалко, Ю. А. "К вопросу выбора оптимальной связи полей дифракционной решетки с поверхностной волной диэлектрического волновода." Thesis, Сумский государственный университет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/43952.
Full textAbstract:
При экспериментальном моделировании электронно-волновых процессов, важным является выбор оптимального расстояния (прицельного параметра) между источником поверхностной волны – диэлектрическим волноводом (ДВ) и дифракционной решеткой (ДР). От величины этого расстояния зависит не только качество связи полей ДР и ДВ, но и угол излучения. В работе указано, что величина прицельного параметра не влияет на величину угла излучения.
28
Malek, Abadi Seyed Ali. "Solutions et matériaux nouveaux pour guide d'onde Térahertz." Thèse, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5914.
Full textAbstract:
Dans cette thèse, une étude approfondie sur des matériaux et des solutions pratiques est réalisée afin de répondre aux difficultés rencontrées dans la propagation des ondes à des fréquences térahertz (THz). Deux matériaux ont été identifiés comme étant prometteur: le graphène et le silicium à haute résistivité (HR-Si). Une première solution, basée sur des guides d’ondes à plaques parallèles (parallel plate waveguide-PPWG) avec des conditions de fermetures conducteur parfait (perfect electric conductor-PEC) -- graphène et graphène -- graphène a été analysée dans un premier temps. En considérant l'excitation du graphène par un champ électrique seulement, puis par un champ électromagnétique statique, les équations de Maxwell ont été résolues sous ces deux conditions et les constantes de propagations des différents modes ont été extraites. La démonstration de l'existence d'un mode propagatif hybride à l'intérieur du guide est faite dès que le graphène est excité par un champ magnétique. De plus, il est montré que l'intensité de chaque type de modes, transverse électrique (TE) ou transverse magnétique (TM), peut être ajustée suivant les champs d'excitation du graphène. Bien que le guide à plaques parallèles utilisant du graphène permette d'avoir des propriétés agiles, soit le contrôle des modes selon l'excitation du graphène, il n'en reste pas moins vrai que la faible conductivité intrinsèque au graphène conduit à un problème d'atténuation importante de l'onde. De plus, la difficulté d'obtenir des couches de graphène de taille adéquate entrave le développement de composants et de circuits fonctionnels, utilisables et à un coût raisonnable. La thèse porte ensuite sur l’étude du silicium haute résistivité pour guider des ondes aux fréquences térahertz. Tout d’abord, un guide composé d'une couche de HR-Si, de section rectangulaire dont la largeur est très grande par rapport à la hauteur, est caractérisé en utilisant un système de spectroscopie dans le domaine du temps, système permettant d'obtenir un large spectre de fréquences dans le domaine THz. Par cette caractérisation, les faibles pertes et la faible dispersion du HR-Si est démontrée. Cependant, il est aussi démontré que la géométrie du guide n'est pas optimale, conduisant à des pertes par dispersion de l'onde à l'intérieur du guide au fur et à mesure de sa propagation. Aussi, pour éviter cette dispersion, un confinement de l'onde est proposé en réduisant la largeur de la couche HR-Si pour la rendre de l'ordre de la hauteur (confinement en x et y, propagation en z) conduisant ainsi à la réalisation d'un guide d’ondes diélectrique en ruban (dielectric ribbon waveguide-DRW). Une analyse approfondie de la propagation d'une telle structure a conduit à concevoir un guide à faibles pertes d'une part, mais également à propagation monomode sur une large bande de fréquence. Une méthode de fabrication simple a été développée pour réaliser ce type de guide et un banc de mesure spécifique a été mis en place pour caractériser ce nouveau guide. Les mesures réalisées utilisent un analyseur de réseaux vectoriel (un PNA-X d'Agilent) auquel est branché deux têtes de mesure de la compagnie Virginia Diode Inc's (VDI) pour obtenir les bandes de fréquences désirées. Les sorties sont alors en guide rectangulaire standard, soit WR-8, soit WR-5 selon la plage de fréquence visée. Les résultats des mesures se comparent très bien avec les simulations réalisées avec un logiciel utilisant la méthode des éléments finis en trois dimensions (HFSS de la compagnie ANSYS) permettant d'obtenir les paramètres de la matrice de diffraction (S) mesurée par l'analyseur de réseau vectoriel. Finalement, dans le chapitre 6, un filtre passe-bande est développé comme preuve de concept pour l'utilisation du guide DRW utilisant le matériau HR-Si. Outre les faibles pertes et la propagation monomode d'un tel guide DRW, il est aussi montré dans cette thèse la facilité du processus de fabrication, le faible coût de ce procédé ainsi que la possibilité d'intégration avec d'autres composants passifs et actifs. Avec toutes ces caractéristiques très intéressantes sur différents plans, le guide DRW en HR-Si apparaît comme une solution très compétitive pour devenir un standard dans la bande de fréquence des THz.
29
Cox, Gavin J. "Techniques for pattern control of a dielectric rod antenna suitable for use in mobile communications." Thesis, Loughborough University, 2002. https://dspace.lboro.ac.uk/2134/12693.
Full textAbstract:
This thesis describes the development of antennas suitable for mobile coinmunication systems based on a dielectric rod antenna fed from circular waveguide. Pattern control of the antenna is implemented using a combination of Frequency Selective Surface (FSS) elements and metallic endcaps placed on the antenna Both linear and circular polarised feeds have been made for these antennas to ensure they are suitable for a wide range of applications. The suitability of the dominant and next, higher order, waveguide mode were investigated and conclusions drawn as to their suitability for this type of antenna. The antennas were extensively modelled using a commercial TLM based solver and the results of these simulations were compared to the comprehensive set of antenna pattern measurements and S-parameter measurements obtained for the prototype antennas.
30
Fevrier, Mickaël. "Couplage entre un guide d’onde diélectrique et un guide à plasmon de surface localisé : conception, fabrication et caractérisation." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112040/document.
Full textAbstract:
Ce travail de thèse présente une étude théorique, numérique et expérimentale de l’intégration sur un guide d’onde diélectrique de chaînes de nanoparticules d’or supportant des résonances « plasmon de surface localisé ». Les guides d’onde à plasmon de surface localisé procurent un confinement sub-longueur d’onde de la lumière, ce qui permet d’envisager la réalisation de composants optiques ultra-compacts. Cependant, leurs pertes optiques élevées restreignent leur application à de courtes distances de propagation, contrairement aux guides d’onde diélectriques. Une combinaison judicieuse des deux types de guide doit donc permettre de bénéficier de leurs avantages respectifs. Dans un premier temps, nous avons étudié théoriquement les propriétés des chaînes des nanoparticules grâce à un modèle analytique basé sur l’approximation de dipôles ponctuels couplés, que nous avons développé. Cette étude a permis de déterminer la forme et les dimensions des nanoparticules qui ont ensuite été introduites dans un logiciel de FDTD pour simuler le couplage entre la chaîne de nanoparticules et le guide diélectrique (SOI ou en Si3N4). De cette étude numérique, nous avons déduit les géométries des structures à fabriquer. Les structures réalisées ont été caractérisées à l’aide d’un banc de transmission résolue spectralement, mis en place pendant cette thèse, et d’un système de mesures en champ proche optique en collaboration avec le LNIO (Troyes). Pour la première fois, nous avons montré expérimentalement les propriétés d’une chaîne courte de nanoparticules intégrée sur un guide SOI, ainsi que le phénomène de guides couplés entre une chaîne longue de nanoparticules et un guide SOI. Une valeur record de la constante de couplage a été obtenue, et ce, aux longueurs d’onde des télécoms (proche infrarouge). L’énergie lumineuse transportée par le mode TE du guide SOI peut ainsi être entièrement transférée au guide plasmonique en 4 ou 5 nanoparticules, soit une distance de propagation de moins de 600 nm. Nous avons également étudié les propriétés de réseaux de Bragg à base de plasmon de surface localisé en confrontant les résultats de mesures de transmission résolue spectralement aux résultats théoriques d’un modèle analytique basé à la fois sur l’approximation de dipôle ponctuel en régime quasi-statique et la théorie des modes couplés. Ces travaux ouvrent la voie à des applications de pinces optiques, de capteurs ou de spaser, qui bénéficieront de l’intégration de nanoparticules métalliques dans les circuits photoniquesThis PhD work presents a theoretical, numerical and experimental study of the integration of a gold nanoparticle chain supporting "localized surface plasmon resonances" on a dielectric waveguide. The localized surface plasmon allows a sub-wavelength confinement of light which could lead to the achievement of ultra-compact optical components. However, the high level of optical losses restricts their application to short propagating distances unlike dielectric waveguides. A judicious combination of both types of guides should therefore allow taking profit of their respective advantages. Firstly, we have theoretically studied the properties of nanoparticles chains using an analytical model that we have developed following the coupled dipoles approximation. This has helped us to determine the shape and size of nanoparticles, which have been further used in a FDTD software, to simulate the coupling between the chain and the dielectric waveguide (SOI or Si3N4). Using this numerical study, we have deduced the geometries of structures to be fabricated. The realized structures have been characterized using a spectrally resolved transmission set-up, built during this thesis, and an optical near field measurement set-up (collaboration LNIO Troyes). For the first time, we have experimentally shown the properties of short nanoparticle chains integrated on a SOI waveguide as well as the existence of a coupled waveguide phenomenon between long nanoparticle chains and SOI waveguides. A record value has been obtained for the coupling constant at telecom wavelengths (near infrared). The light energy carried by the TE mode of the SOI waveguide can be completely transferred into the plasmonic waveguide via the first 4 or 5 nanoparticles of the chain, which means a distance of less than 600 nm. We have also studied the properties of Bragg gratings based on localized surface plasmon. Experimental results from spectrally resolved transmission measurements have been compared to theoretical results obtained from an analytical model based on the point dipole approximation in quasi-static regime, on one hand, and using the coupled mode theory, on the other hand. This work opens the way for applications to optical tweezers, sensors or spasers, which will benefit from the integration of metal nanoparticles in photonic circuits
31
Ismail, Alhzzoury Ahmad. "Contribution à la modélisation des structures SIW et SINRD pour application micro-ondes et télécommunication." Phd thesis, Toulouse, INPT, 2013. http://oatao.univ-toulouse.fr/9701/1/ismail_alhzzoury.pdf.
Full textAbstract:
Les développements technologiques en télécommunication et microondes tendent depuis plusieurs années vers la miniaturisation des circuits, une réduction des coûts, des masses et des pertes dans ces dispositifs. Les circuits SIW (Substrate Integrated Waveguide) s’inscrivent tout à fait dans cette mouvance et font à l’heure actuelle l’objet de nombreux sujets de recherche avec des applications directes dans l’industrie. Les circuits SINRD (Substrate Integrated Non Radiative Dielectric) utilisent eux les propriétés du substrat usiné (insertion de trous) pour la propagation du signal et des fonctions de l’électronique peuvent également être développées avec cette technologie. La conception de ces circuits passe généralement par des outils peu performants car non dédiés. Dans ce travail de thèse, une méthode numérique dédiée à ces circuits est développée. Elle est validée par comparaison à d’autres méthodes numériques et des mesures. Elle présente des temps de calcul très faibles. De nouveaux dispositifs pour des applications en télécommunications spatiales bas coûts et faibles pertes peuvent ainsi être développés grâce à elle.
32
Петровський, Михайло Васильович, Михаил Васильевич Петровский, Mykhailo Vasylovych Petrovskyi, Геннадій Савелійович Воробйов, Геннадий Савельевич Воробьев, Hennadii Saveliiovych Vorobiov, Олександр Сергійович Кривець, et al. "Электродинамические характеристики системы экранированных диэлектрических волноводов с распределеной связью." Thesis, Вебер, 2013. http://essuir.sumdu.edu.ua/handle/123456789/38337.
Full textAbstract:
Методами численного и экспериментального моделирования показана возможность реализации механического и электронного способов управления электродинамическими характеристиками при помощи изменения параметров проводящих экранов в функциональных устройствах выполненных на базе связанных диэлектрических волноводов.The present paper concerns a possibility of implementation of the mechanical and electronic control methods for the electrodynamics characteristics of functional devices which based on coupled dielectric waveguides by means of changes in the parameters of conductive screens according to numerical and experimental simulation.
33
Kim, Jinkee. "Analysis of optical waveguide discontinuities and design of planar prisms in waveguides." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/13878.
Full text
34
Teplý, Tomáš. "Modelování mikrovlnných struktur na bázi SIIG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219858.
Full textAbstract:
Well-known dielectric image guide reach in millimeter-wave interesting results. Compared to a conventional types of lines and waveguides is characterised by low-through loss for frequencies approaching 100 GHz. This work is detail focused to basic characteristics and especially type of perforate highpermitivity substrate for obtain implemented waveguide to dielectric board (SIIG). The work also contains couple suggestions for various transitions from a commonly used lines and waveguides. Simulation results using finite element method is achieved attenuation values below 2 dB, which corresponds to a 2 cm length and include a waveguide itself with a pair of transitions. Finally, this work also designed the production method and SIIG applicatoin in practicle.
35
Рибалко, Олександр Олександрович, Александр Александрович Рыбалко, and Oleksandr Oleksandrovych Rybalko. "Моделирование электромагнитных явлений в многосвязных квазиоптических системах с периодическими неоднородностями." Thesis, Изд-во СумГУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20904.
Full textAbstract:
Дисертаційна робота присвячена встановленню загальних
закономірностей фізики хвильових процесів в багатозв’язних квазіоптичних системах (БКС), на основі яких дані рекомендації щодо використання оптимальних режимів збудження БКС у практичних схемах приладів НВЧ.
У літературному огляді проаналізовано сучасний рівень розвитку і
основні типи класичних багатозв’язних систем, приведена їх класифікація.Розроблена загальна методика і функціональна схема моделювання електро-магнітних явищ в БКС, яка реалізована в частотному діапазоні f = 30 − 80 ГГц.
У результаті системного дослідження випромінюючих систем БКС різноманітних модифікацій встановлено: можливість фазової і амплітудної корекції інтенсивності випромінювання шляхом зміни координатної і кутової орієнтації двохрядних металевих ґраток, відносно осі діелектричного хвилеводу; визначені умови резонансного випромінювання при зміщенні ламелів
напівпрозорих решіток на величину "d ≈ λ 2 і відбивних решіток на "d ≈ λ 4 .
Показано, що при включенні в об’єм напівсферичного відкритого резонатора двухрядних металевих дифракційних решіток, смуга пропускання БКС в області резонансної частоти зростає в 3-4 рази при одночасному пригніченні коливань на бокових частотах. Встановлені межі впливу циклотронного параметру на інкременти зростання амплітуд поля в відкритому хвилеводі.
Запропоновані і реалізовані в експерименті нові схеми пристроїв НВЧ.
При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/20904Диссертационная работа посвящена установлению общих закономерностей физики волновых процессов в многосвязных квазиоптических системах (МКС), на основе которых даны рекомендации по использованию оптимальных режимов возбуждения многосвязных квазиоптических систем в практических схемах устройств СВЧ. На основании литературного обзора проанализирован современный уровень развития и основные типы классических многосвязных систем, сформулировано их определение. Приведена классификация таких систем, обозначены основные объекты теоретических и экспериментальных исследований, а также задачи, решаемые в диссертационной работе. Разработаны общая методика и функциональная схема моделирования электромагнитных явлений в МКС, которые базируются на преобразовании поверхностных волн диэлектрического волновода (ДВ) в объемные при их распространении вдоль периодических металлических и металлодиэлектрических структур (МДС). Экспериментальное моделирование электромагнитных процессов в МКС реализовано в частотном диапазоне f = 30 − 80 ГГц. В результате системного исследования излучающих структур МКС различных модификаций установлен ряд новых эффектов в преобразовании поверхностных волн в объемные на периодических неоднородностях сложной конфигурации: для двухрядных металлических дифракционных решеток (ДР) установлена возможность фазовой и амплитудной коррекции интенсивности излучения путем смещения их ламелей относительно продольной оси ДВ, либо изменения угловой ориентации решеток относительно этой оси; определены условия резонансного излучения при смещении ламелей полупрозрачных решеток на величину "d ≈ λ 2 и отражательных решеток при значениях "d ≈ λ 4 ; для двухрядной системы отражательная – полупрозрачная ДР установлена возможность увеличения интенсивности трансформации поверхностной волны в объемную на 30 – 40% по сравнению с однорядными системами; установлена корреляция численного и экспериментального моделирования на излучающих системах с МДС. Показано, что при включении в объем полусферического ОР двухрядных металлических ДР, полоса пропускания МКС в области резонансной частоты увеличивается в 3 – 4 раза при одновременном подавлении колебаний на боковых частотах. Для МКС с периодическими металлодиэлектрическими структурами установлена возможность управления частотными и амплитудными характеристиками при изменении их электродинамических параметров. Для волноведущих МКС в рамках линейной теории усилителя на эффекте Смита-Парселла установлены пределы влияния циклотронного параметра на инкременты нарастания амплитуд поля в открытом волноводе (ОВ). Определены оптимальные условия формирования бегущей электромагнитной волны вдоль оси ОВ при различной комбинации конфигураций зеркал и излучающих систем. Показана возможность разделения мощностей падающей и отраженной волн в результате их интерференции в объеме ОВ при наличии двух дифракционо-связанных источников излучения. В результате проведенных исследований предложены и реализованы в эксперименте перестраиваемые направленные ответвители на дифракционно-связанных линиях передачи, которые не уступают по параметрам лучшим образцам существующих ответвителей на основе ДВ, а также делители мощности на основе двухрядных ДР. Предложены схемы источников излучения на основе МКС, определена возможность их реализации при переходе в субмиллиметровый – инфракрасный диапазоны волн. При цитировании документа, используйте ссылку http://essuir.sumdu.edu.ua/handle/123456789/20904
Dissertation is devoted to establishment of physics of wave processes in multilinked quasi-optical structures (MQS), on the basis of which recommendations for using best performances of multilinked quasi-optical structures stimulation in practical systems of microwave frequency are given. On the grounds of literary review modern level of development and basic types of classical multilinked systems are analyzed and their classification is given. The common principles and functional scheme of electromagnetic phenomena modeling in MQS, which is realized in frequency range f = 30 − 80 GHz, are worked out. As the result of system investigation of radiant systems MQS of different modifications is established: the possibility of phase and amplitude correction of radiation intensity; conditions of resonance radiation while displacement of translucent grid segments on the magnitude "d ≈ λ 2 and reflecting gratings with the value "d ≈ λ 4 . It is shown, that while brining in volume of hemispheric open resonator (OR) two-column metal diffraction grid the bandwidth of MQS in resonator frequency becomes 3-4 times more, while simultaneous suppression of vibrations on side frequency. The influence limits of cyclotron parameter on the increments of field amplitude growth in the open waveguide are determined. New schemes of high frequency devices are proposed and realized in experiment. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/20904
36
Петровський, Михайло Васильович, Михаил Васильевич Петровский, Mykhailo Vasylovych Petrovskyi, Геннадій Савелійович Воробйов, Геннадий Савельевич Воробьев, Hennadii Saveliiovych Vorobiov, Олександр Олександрович Рибалко, et al. "Селективные свойства двухрядных периодических структур миллиметрового диапазона волн." Thesis, Вебер, 2014. http://essuir.sumdu.edu.ua/handle/123456789/38324.
Full textAbstract:
Представлены результаты моделирования преобразования поверхностных волн диэлектрического волновода в объемные на двухрядных периодических структурах различных модификаций. Показана возможность эффективной регулировки мощности излучаемых гармоник и селекции колебаний для исследуемых структур.The results of modeling transformation of surface waves of a dielectric waveguide into spatial waves on different modifications of the double-row periodic structures are presented. Possibility of effective radiated power control of harmonics and selection of oscillations for the investigated structures is shown.
37
Kubín, Petr. "Dielektrická rezonátorová anténa na bázi vlnovodu integrovaného do substrátu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220271.
Full textAbstract:
The Master’s thesis deals with the design of the dielectric resonator antenna array based on the substrate integrated waveguide. The work describes various feed methods of the dielectric resonator antenna and the technique of the design of the antenna. The antenna array was designed in the simulative program ANSYS HFSS at the frequency 10 GHz, subsequently fabricated and measured. The antenna array has the bandwidth of 570 MHz for S11 better than –10 dB and the gain of 12.1 dBi.
38
Bruno, William M. Bridges William B. "Powder core dielectric waveguides /." Diss., Pasadena, Calif. : California Institute of Technology, 1986. http://resolver.caltech.edu/CaltechETD:etd-03192008-084301.
Full text
39
Gasi, Jasmin. "Design, Fabrication and Validation of High-permittivity Low-loss Microwave Material for Biomedical Sensor." Thesis, Uppsala universitet, Fasta tillståndets elektronik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-364035.
Full textAbstract:
Abstract The purpose of this task is to synthesize a dielectric substrate material through a sintering process, which can be used for non-invasive physiological sensor development. Low loss, high dielectric constant ceramic material is used. Sintering process is employed to ensure stable structure and homogeneous dielectric properties of the substrate. Samples were prepared with TiO2 and in combination with CuO and Al2O3. All samples were measured and validated in 500 MHz to 20 GHz frequency range. Characterization measurements were performed with a Vector Network Analyzer, FieldFox N9918A, and connected to Keysight, open ended coaxial probe and performance probe. Reflection based measurement method was used due to its simplicity, speed and requirement of wideband data. The dielectric measurement results of developed samples show non-frequency dispersive behaviour, high dielectric constant and data was also selected at 2.45 GHz in aligned to the industrial, scientific and medical band. The resulting measurements show the highest dielectric constant of 16.6 at 2.45 GHz with a very low loss behaviour.Målet är att syntetisera ett material, genom sintringsprocess, som kan användas som ett dielektriskt substrat för utveckling av sensorer. Det dielektriska materialet har keramisk materialstruktur och innehar högt dielektricitetskonstant med låga dielektriska materialförluster. Denna uppgift kräver att dielektriska materialet ska vara stabilt och inneha isotropiska egenskaper efter att genomgått sintringsprocess. Proverna förberedes med TiO2 och även i kombination med TiO2 tillsammans med CuO och Al2O3. Proverna mäts i frekvensområdet 500 MHz till 20 GHz. Mätningarna utförs med Vector Network Analyzer, FieldFox N9918A från Keysight. Resultat som visas och jämförs i arbetet är tagna vid 2.45 GHz eftersom det används och är standardiserat för medicinskt frekvensband. Högsta uppmätta dielektricitetskonstant har värdet av 16,6. Resultaten visar även låga förluster i dielektrikumet.
40
Ismail, Alhzzoury Ahmad. "Contribution à la modélisation des structures SIW et SINRD pour application micro-ondes et télécommunications." Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2013. http://tel.archives-ouvertes.fr/tel-00871985.
Full textAbstract:
Les développements technologiques en télécommunication et microondes tendent depuis plusieurs années vers la miniaturisation des circuits, une réduction des coûts, des masses et des pertes dans ces dispositifs. Les circuits SIW (Substrate Integrated Waveguide) s'inscrivent tout à fait dans cette mouvance et font à l'heure actuelle l'objet de nombreux sujets de recherche avec des applications directes dans l'industrie. Les circuits SINRD (Substrate Integrated Non Radiative Dielectric), utilisent eux les propriétés du substrat usiné (insertion de trous) pour la propagation du signal et des fonctions de l'électronique peuvent également être développées avec cette technologie. La conception de ces circuits passe généralement par des outils peu performants car non dédiés. Dans ce travail de thèse, une méthode numérique dédiée à ces circuits est développée. Elle est validée par comparaison à d'autres méthodes numériques et des mesures. Elle présente des temps de calcul très faibles. De nouveaux dispositifs pour des applications en télécommunications spatiales bas coût et faibles pertes peuvent ainsi être développés grâce à elle.
41
Zechmeister, Jaroslav. "Anténní systém pro automobilový radar." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-377020.
Full textAbstract:
This thesis deals with the design of lens antennas for automotive radar in 77 GHz bandwidth. The work explains methods of designing waveguides as well as horn antennas and dielectric lens. A simulation of three designed horn antennas is performed in CST Microwave Studio. Antennas with spherical and hyperbolical lens are simulated as well and subsequently optimized for maximal gain. The thesis also investigates effects of the lens permittivity on its properties. Furthermore, the work deals with a design of an antenna system with minimalized antenna coupling. Nylon, ABS and photopolymer lens are designed and compared afterwards. ABS and photopolymer lens were produced by 3D print
42
Рубан, Анатолій Іванович, Анатолий Иванович Рубан, Anatolii Ivanovych Ruban, Михаил Васильевич Петровский, Михайло Васильович Петровський, Mykhailo Vasylovych Petrovskyi, Ольга Владимировна Прокопчук, et al. "Электродинамические характеристики двухрядных периодических систем." Thesis, Сумский государственный университет, 2017. http://essuir.sumdu.edu.ua/handle/123456789/64228.
Full textAbstract:
В настоящее время значительный интерес для создания многосвязных широкополосных систем представляют процессы преобразования поверхностных волн в объемные на двухрядных дифракционных решетках (ДР) при возбуждении их диэлектрическим волноводом (ДВ). Простейшим вариантом двухрядной системы является сочетание решеток из брусьев прямоугольного сечения, расположенных вдоль оси ДВ.
43
Lu, Tao. "Boundary element analysis of dielectric waveguides." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0007/MQ36050.pdf.
Full text
44
QUEVEDO, CLAUDIA PEREIRA. "ANALYSIS OF WAVEGUIDES WITH DIELECTRIC LOADING." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1991. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=8841@1.
Full textAbstract:
TELECOMUNICAÇÕES BRASILEIRAS S/ANeste trabalho são analisados os campos modais em guias circulares contendo em seu eixo um carregamento cilíndrico dielétrico uniforme ou corrugado, identificando propriedades destes campos úteis a aplicações no projeto de ressoadores, filtros e alimentadores. Com o objetivo de apresentar uma aplicação da análise dos guias circulares com carregamento dielétrico, é feita a análise de um ressoador dielétrico cilíndrico apresentando- se sua carta modal relacionando suas freqüências de ressonância com o carregamento dielétrico.
In this work the modal fields for circular waveguides with uniform or corrugated dieletric loads are analysed, and useful properties of these fields to applications such as ressonators, filters and antenna feeders are ecamined. As an application of the analysis of dieletric loaded circular waveguides, an algorithm is developed for the determination of ressonant frequencies of dieletric loaded ressonators, and the modal chart, relating ressonant frequencies to ressonator dimensions, is evaluated.
45
Knoesen, André. "Guided modes in anisotropic dielectric planar waveguides." Diss., Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/14898.
Full text
46
Dods, Steven R. A. "A spectral theory for planar dielectric waveguides." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30690.
Full textAbstract:
The problem of electromagnetic wave propagation across the junction of two similar planar
dielectric waveguides is analysed, within the Kirchhoff approximation, by expanding the field into transverse variations of all possible modes. It is proven that the expansion can represent any solution for any planar dielectric waveguide. The spectral function is introduced into the representation, and this helps resolve some of the theoretical problems in passing from the limit of closed waveguides to open waveguides. Using the spectral function and the Gel'fand-Levitan integral equation some new exact solutions to novel dielectric planar waveguides can be found. Examples of waveguiding by total internal reflection or by Bragg reflection (which are physically very different processes) can be generated by changing a single parameter in the formulation. Usually the representation
for an open dielectric waveguide requires the matrix spectral function. However the Gel'fand-Levitan reconstruction is defined for scalar spectral functions. A technique for constructing the spectral matrix and the scattering solutions from two spectral functions is demonstrated. This technique uses a variational formulation of a scattering experiment. The connection between a dielectric structure and the characteristics of propagation on it is obscure. However the connection between these characteristics and the spectral function
is much clearer. It is sometimes possible to make predictions about the properties of the waveguide by looking at its spectral function only. Since the connection between the spectral function and the dielectric structure is well established by inverse spectral theory, introducing the spectral function has been of help in establishing the desired connection between the dielectric structure and the characteristics of propagation on it.
Such considerations suggest one of the above waveguides is sensitive to small perturbations
and could be used as an electro-optic modulator. Detailed calculations confirm the hypothesis.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
47
Modoran, Andrei V. "Classical and quantum dynamics of atomic systems in the proximity of dielectric waveguides." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1164654528.
Full text
48
Lawson, Robert Chester. "A study of periodic gratings in planar dielectric waveguides." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-05022009-040647/.
Full text
49
Pennock, S. "Topics in the plasmatic control of dielectric waveguides." Thesis, University of Bath, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374839.
Full text
50
Mametsa, Henri-Jose. "Contribution à l'étude de nouvelles structures de filtrage utilisant des guides d'ondes rectangulaires à section droite inhomogène." Brest, 1987. http://www.theses.fr/1987BRES2020.
Full textAbstract:
Synthèse, analyse et réalisation de nouvelles structures de filtrages utilisant des sections de guides d'ondes et des inserts diélectriques; ceux-ci étant interchangeables et facilement usinables, il suffit, avec la même structure de guides métalliques, de calculer les dimensions des inserts pour réaliser la fonction désirée, d'où une technologie à faible coût.