Dissertations / Theses on the topic 'Radiating'
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Rosenlind, Johanna. "The Impulse-Radiating Antenna." Thesis, Karlstad University, Faculty of Technology and Science, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-4527.
Full textAs the interest in intentional electromagnetic interference (IEMI) increases, so does the need of a suitable antenna which endures those demanding conditions. The ultrawideband (UWB) technology provides an elegant way of generating high-voltage UWB pulses which can be used for IEMI. One UWB antenna, invented solely for the purpose of radiating pulses, is the impulse radiating antenna (IRA). In the course of this master thesis work, a suitable geometry of the IRA is suggested, and modelled, for the high-voltage application of 90 kV.
Karaismail, Ertan. "Numerical Simulation Of Radiating Flows." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606452/index.pdf.
Full textKamenkovich, Igor V. "Radiating instability of nonzonal ocean currents." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/54424.
Full textIncludes bibliographical references (leaves 192-195).
by Igor V. Kamenkovich.
Ph.D.
Lakkis, Issam Adnan 1970. "Lagrangian computations of radiating fire plumes." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/89262.
Full textAgunlejika, Oluwafunmilayo. "Efficient discrete modelling of axisymmetric radiating structures." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/21714.
Full textDillon, Bernice Mary. "Finite element analysis of radiating waveguide discontinuities." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357770.
Full textLuettgen, Mark R. (Mark Robert). "Trajectory estimation of an optically radiating source." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/14027.
Full textIncludes bibliographical references (leaves 115-117).
by Mark R. Luettgen.
M.S.
Andera, Craig. "Trajectory estimation of an optically radiating source." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36634.
Full textCharnley, Debra. "Radiating flamelet models of turbulent buoyant diffusion flames." Thesis, University of Southampton, 1986. https://eprints.soton.ac.uk/52291/.
Full textToalá, Enríquez Rosemberg. "Stationarity of asymptotically flat non-radiating electrovacuum spacetimes." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/89265/.
Full textAli, Hassan O. "Finite-element time-domain analysis of axisymmetrical radiating structures." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7897.
Full textCox, Daniel Paul Goodhall. "Black holes and radiating bodies in non-flat backgrounds." Thesis, Queen Mary, University of London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497899.
Full textMcColl, Iain. "Radiating and coupling elements in waveguide planar array antennas." Thesis, Heriot-Watt University, 1992. http://hdl.handle.net/10399/788.
Full textRichards, John A. (John Alfred). "Time-to-intercept estimation for an optically radiating source." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/41391.
Full textIncludes bibliographical references (leaves 93-94).
by John A. Richards.
M.Eng.
Fuscaldo, Walter. "Advanced radiating systems based on leaky waves and nondiffracting waves." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S015/document.
Full textIn recent years, microwave, millimeter-wave, and THz applications such as medical and security imaging, wireless power transfer, and near-field focusing, just to mention but a few, have gained much attention in the area of ICT due to their potentially high social impact. On one hand, the need of highly-directive THz sensors with tunable radiating features in the far-field region has recently boosted the research activity in the design of flexible, low-cost and low-profile devices. On the other hand, it is of paramount importance to focus energy in the near-field region, and thus the generation of limited-diffraction waves in the microwave and millimeter-wave regime is a topic of recent increasing interest. In this context, leaky-wave theory is an elegant and extremely useful formalism which allows for describing in a common fashion guiding and radiating phenomena in both the near field and the far field, spanning frequencies from microwaves to optics passing through THz. In this PhD thesis we aim to exploit the intrinsic versatility of the leakywave approach to design advanced radiating systems for controlling the far-field radiating features at THz frequencies and for focusing electromagnetic radiation in the near field at millimeter waves. Specifically, the use of relatively new materials such as graphene and liquid crystals has been considered for the design of leaky-wave based radiators, achieving very promising results in terms of reconfigurability, efficiency, and radiating capabilities. In this context, an original theoretical analysis has provided new general formulas for the evaluation of the radiating features (e.g., half-power beamwidth, sidelobe level, etc.) of leaky-wave antennas. Indeed, the current formulations are based on several simplifying hypotheses which do not allow for an accurate evaluation of the beamwidth in different situations. In addition to the intriguing reconfigurable capabilities offered by leaky waves in far-field applications, interesting focusing capabilities can be obtained in the near field. In particular, it is shown that leaky waves can profitably be used to generate limited-diffraction Bessel beams by means of narrow-band radiators in the microwave range. Also, the use of higherorder leaky-wave modes allows for achieving almost the same performance in the millimeter-wave range, where previous designs were subjected to severe fabrication issues. Even more interestingly, the limited-diffractive character of Bessel beams can also be used to generate limited-diffraction pulses as superpositions of monochromatic Bessel beams over a considerable fractional bandwidth. In this context, a novel theoretical framework has been developed to understand the practical limitations to efficiently generate limited-diffraction, limited-dispersion pulses, such as X-waves, in the microwave/millimeter-wave range. As a result of this investigation, a class of wideband radiators has been thoroughly analyzed, showing promising capabilities for the generation of both zeroth-order and higher-order Xwaves. The latter may pave the way for the first localized transmission of orbital angular momentum in the microwave range
Ireland, David John, and n/a. "Realization of Dielectric Embedded Monopole Radiating Structures For Wireless Computing." Griffith University. School of Microelectronic Engineering, 2006. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070117.175717.
Full textSchlub, Robert Walter, and n/a. "Practical Realization of Switched and Adaptive Parasitic Monopole Radiating Structures." Griffith University. School of Microelectronic Engineering, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040610.112148.
Full textBaretela, Michael J. "Increasing prompt response from impulse radiating antenna by aperture shaping." Thesis, Monterey California. Naval Postgraduate School, 2002. http://hdl.handle.net/10945/6094.
Full textIn order to improve the prompt response from an impulse radiating antenna (IRA)number of studies have suggested controlling the spatial distribution of the aperture fields by changing the feed arm angle. Other work has suggested that proper shaping of the aperture can further enhance the radiated signal for a given feed structure. This paper shows how the radiated prompt response can be maximized for a given feed arm configuration by shaping the aperture to eliminate fields orientated in the wrong direction. The percent increase in the prompt radiated electric field for a 200 . IRA with a ideally shaped aperture compared to a standard circular aperture ranged from 0.42% to 39.94% depending on the input electrode angle. For the most common electrode angles of 45Ê» and 60Ê» the increases are 6.00% and 16.63% respectively.
Buxton, Carey G. "Design of a Broadband Array Using the Foursquare Radiating Element." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/28363.
Full textPh. D.
Ireland, David John. "Realization of Dielectric Embedded Monopole Radiating Structures For Wireless Computing." Thesis, Griffith University, 2006. http://hdl.handle.net/10072/367819.
Full textThesis (Masters)
Master of Philosophy (MPhil)
School of Microelectronic Engineering
Full Text
Schlub, Robert Walter. "Practical Realization of Switched and Adaptive Parasitic Monopole Radiating Structures." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/366803.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Microelectronic Engineering
Full Text
Partal, Hakan Pasa. "Circular loop antennas radiating in the presence of symmetrically placed scatterers." 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 textXu, Xin. "MODULAR FAST DIRECT ANALYSIS USING NON-RADIATING LOCAL-GLOBAL SOLUTION MODES." UKnowledge, 2008. http://uknowledge.uky.edu/gradschool_diss/690.
Full textBrooks, David Hamilton. "On the radiating and dynamic properties of the solar upper atmosphere." Thesis, University of Strathclyde, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415098.
Full textFoster, Adam. "On the behaviour and radiating properties of heavy elements in fusion plasmas." Thesis, University of Strathclyde, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501815.
Full textCook, Gregory Gildroy. "High resolution three dimensional imaging of the current distributions on radiating structures." Thesis, University of Sheffield, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431745.
Full textDumont, Joey. "On the modelization of optical devices: from dielectric cavities to radiating structures." Master's thesis, Université Laval, 2014. http://hdl.handle.net/20.500.11794/25371.
Full textIn this essay, we will develop different modelization techniques valid for bidimensional dielectric cavities having arbitrary geometries and refractive index profiles and provide a way to accurately compute the resonances of such structures. The refractive index thus becomes an additional design variable for dielectric cavities. A numerical analysis of of the underlying equations of the theory will reveal that perhaps it is best to forego differential equations in favour of integral ones for the scattering problem. In the second part, we will discuss the modelization of radiating structures. Using the formalism developed in the previous section, we will study the lasing properties of bidimensional cavities using the newly developed self-consistent ab initio laser theory (SALT). We will also touch on the modelization of the class of antenna known as leaky coax
Uygur, Ahmet Bilge. "A Non-iterative Pressure Based Algorithm For The Computation Of Reacting Radiating Flows." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608274/index.pdf.
Full textwere benchmarked against experimental data and numerical solutions available in the literature and the capability of the code to predict transient solutions was demonstrated on these test cases. Favorable agreements were obtained for both test cases. The effect of radiation and non-gray treatment of the radiative properties were investigated on the second test case. It was found that incorporation of radiation has significant effect on Temeprature and velocity fields but its effect is limited in species predictions. Executions with both radiation models revealed that the non-gray radiation model considered in the present study produces similar results with the gray model at a considerably higher computational cost. The algorithm developed was found to be an efficient and versatile tool for the timedependent simulation of different flow scenarios constitutes the initial steps towards the computation of transient turbulent combustion.
Kim, Kangwook. "Numerical and experimental investigation of impulse-radiating antennas for use in sensing applications." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/14944.
Full textKojima, Seishiro. "Novel Beamforming and Antenna Techniques for Microwave Power Transmission in Radiating Near Field." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263667.
Full textEmidio, Fernando. "Analysis of multidimensional radiating structures by the spatial Fourier transform and computational electromagnetics." Thesis, Saint-Etienne, 2013. http://www.theses.fr/2013STET4011.
Full textThis manuscript presents the research work in the analysis and synthesis of multidimensional radiating structures using an approach that combines Method of Moments and Spatial Fourier Transform. The source distribution (electric current) and radiation pattern are related by the spatial Fourier Transform - Fourier Relation theory (FR). Current distribution is determined using Computational Electromagnetics (CEM), namely Method of Moments (MoM). Previous work using FR theory was done by other authors on linear arrays – uniformly or nonuniformly spaced elemental radiators laid on a straight line. Present work expands FR theory to two and three dimensions on real-world structures. By using MoM we can take into account wire radius, excitation on any point (voltage generator or incident wave) and mutual coupling between elements, thus creating a realistic electromagnetic model for the antenna structure
Moslemi, Parisa. "Design, fabrication, and test of a radiating element for a KU-BAND smart antenna." Mémoire, École de technologie supérieure, 2012. http://espace.etsmtl.ca/1107/7/MOSLEMI_Parisa.pdf.
Full textCohen, Brian S. Ph D. Massachusetts Institute of Technology. "Multidisciplinary design of thermally radiating structures using a level set based topology optimization approach." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/119287.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (pages 267-282).
The need for efficient thermally radiating structures for aerospace applications is apparent in many system designs including satellites, launch vehicles and hypersonic aircraft. While multidisciplinary structural optimization methods have been employed to design these systems, few have incorporated thermal radiation as part of their multi-physics analysis capability. Moreover, with the rapid advancement of manufacturing technologies, the ability to fabricate flight hardware with unprecedented geometric complexity has challenged the limits of human design intuition. As a result, there is a critical need for free-form design methods to harness the full potential of these new manufacturing techniques. This thesis presents a level set based topology optimization approach for designing thermally efficient radiating structures considering multiple objectives, constraints and disciplines. Level set based methods offer a key advantage of defining crisp structural boundaries while seamlessly handling complex geometric transformations. The first contribution of this thesis is deriving a shape sensitivity of the thermal heat power radiated objective function using the adjoint method. This sensitivity is a necessary ingredient for our gradient-based algorithm. The second contribution is developing a topology optimization framework capable of handling multiple objectives and constraints via the augmented Lagrangian method. Both von Mises stress and first mode frequency constraints are implemented since they are commonly found in aerospace design problems where severe structural loads can lead to catastrophic failure. The final contribution is testing several data mining techniques to identify prominent topological features of a large set of designs found using our topology optimization approach. The CUR matrix decomposition is best suited for identifying the principal designs and also aids in categorizing the solution topologies. These contributions are demonstrated on several 2D example problems where the goal is to identify thermally efficient radiating structures able to reject heat using limited material. Both von Mises stress and first mode frequency constraints are enforced to ensure that solutions are sufficiently rigid. The results indicate that many locally optimal solutions exist in the design tradespace with topologically diverse features. Additionally, we show that the thermal compliance objective function commonly used to design conductive structures is not sufficient when a radiating surface exists.
by Brian S. Cohen.
Ph. D.
Iliopoulos, Ioannis. "Engineering the near field of radiating systems at millimeter waves : from theory to applications." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S165.
Full textWith the demand for near-field antennas continuously growing, the antenna engineer is charged with the development of new concepts and design procedures for this regime. From the microwave and up to terahertz frequencies, a vast number of applications, especially in the biomedical domain, are in need for focused or shaped fields in the antenna proximity. This work proposes new theoretical methods for near-field shaping based on different optimization schemes. Continuous radiating planar apertures are optimized to radiate a near field with required characteristics. In particular, a versatile optimization technique based on the alternating projection scheme is proposed. It is demonstrated that, based on this scheme, it is feasible to achieve 3-D control of focal spots generated by planar apertures. Additionally, with the same setup, also the vectorial problem (shaping the norm of the field) is addressed. Convex optimization is additionally introduced for near-field shaping of continuous aperture sources. The capabilities of this scheme are demonstrated in the context of different shaping scenarios. Additionally, the discussion is extended to shaping the field in lossy stratified media, based on a spectral Green's functions approach. Besides, the biomedical applications of wireless power transfer to implants and breast cancer imaging are addressed. For the latter, an extensive study is included here, which delivers an outstanding improvement on the penetration depth at higher frequencies. The thesis is completed by several prototypes used for validation. Four different antennas have been designed, based either on the radial line slot array topology or on metasurfaces. The prototypes have been manufactured and measured, validating the overall approach of the thesis
Ross, Bradley W. "Attenuation of Low Frequency Structurally Radiated Noise With an Array of Weak Radiating Cells." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36555.
Full textMaster of Science
Kumar, Saurabh. "Radiating Macroscopic Dark Matter: Searching for Effects in Cosmic Microwave Background and Recombination History." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1606996786558263.
Full textKitts, Zachary Todd. "An Analytical Study of the Weak Radiating Cell as a Passive Low Frequency Noise Control Device." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/35507.
Full textMaster of Science
Tang, Ming-Chun, Ting Shi, and Richard W. Ziolkowski. "Electrically Small, Broadside Radiating Huygens Source Antenna Augmented With Internal Non-Foster Elements to Increase Its Bandwidth." IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2017. http://hdl.handle.net/10150/623616.
Full textBöttcher, Maximilian A. [Verfasser]. "Design of an active direct radiating array antenna for regional coverage in the Ka-band / Maximilian A. Böttcher." München : Verlag Dr. Hut, 2019. http://d-nb.info/120216918X/34.
Full textLaPean, James William. "Analysis of infinite arrays of arbitrarily shaped planar radiating elements using a Floquet mode based Method of Moments approach." Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-06062008-152047/.
Full textSarray, Sadreddine. "Proposed Revisions to Procedures for Testing and Evaluating Radiating Noise Sources from Small Firearms, including the ANSI/ASA S12.42-2010 Procedure." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40549.
Full textWatkins, Richard. "The impact of the urban environment on the energy used for cooling buildings." Thesis, Brunel University, 2002. http://bura.brunel.ac.uk/handle/2438/5553.
Full textGelmini, Angelo. "Advanced Analysis and Synthesis Methods for the Design of Next Generation Reflectarrays." Doctoral thesis, Università degli studi di Trento, 2019. http://hdl.handle.net/11572/243312.
Full textAmpadu, Boateng Derrick. "Kinetics of Formation and Oxidation of 8-oxo-7,8-dihydroguanine (8oxoG)." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2314.
Full textChristidis, Nikolaos. "Halocarbon radiative forcing in radiation and general circulation models." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312563.
Full textMatthysen, Nardus. "Time domain metrology for MeerKAT systems." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95963.
Full textENGLISH ABSTRACT: This work in this study covers a powerful technique to derive propagation and scattering information in an expedient fashion. Expedient because time-domain (TD) data gathers a broad spectrum in a single transmitted pulse. TD has been criticised because of a lack of dynamic range, which has now been overcome by the direct sampling system, RATTY and RTA. This study focuses on the investigation of a TD metrology system, to assist with the characterisation of MeerKAT systems. The elementary components of the system include a fast-rising impulse generator that was coupled with an impulse radiating antenna (IRA). The system was calibrated and tested before practical measurements and preliminary testing in the Karoo were done. For TDmetrology a larger bandwidth accelerates measurements without the loss of accuracy. The pulse generator’s (PG’s) fundamental components are an avalanche transistor and a step recovery diode (SRD), to sharpen the leading edge of the pulse. Improving the rise-time of a pulse increases its bandwidth in the spectrum. The external circuitry around these components is pivotal and it determines the shape, amplitude and rise-time of the pulse. In the course of the investigation, the general circuitry around the PG was improved to obtain the best possible pulse for measurements inside a reverberation chamber (RC) and for measurements in the Karoo. In light of this, a second and third PG source were obtained. For measurements in the Karoo, a larger amplitude pulse was required to increase the spectral content and this is essential for propagation measurements over distance and the shielding effectiveness (SE) of structures. Stacking avalanche transistors allow larger amplitude pulses and it improves the dynamic range of the spectrum. A PG incorporating stacked avalanche transistors, was designed, built and measured to assist with RC and small-scale field measurements in the Karoo. The third PG was bought for the practical measurements in the Karoo. The PG produces kilovolt pulses with pico-second rise-times that extend the spectral range of the current PGs at our disposal. With these PGs, an antenna is required for the radiation of impulse-like transients. The IRA is a high-gain large-bandwidth antenna. The IRA consists of a parabolic reflector, conical-plate transmission lines that are terminated through resistors onto the dish, and a feeding balun. The IRA design was thoroughly discussed and a first model for metrology was designed, measured and optimised. The IRA was also simulated with computation software code, FEKO. Before deployment of theTDsystem, calibration and characterisation measurements are required. The measuring devices used within this study were sampling oscilloscopes and direct sampling systems. The limitations of each device were explored and are discussed. The final measurements that were conducted contribute to work related to the SKA. This incorporated antenna pattern calibration, propagation over distance and the SE of a berm built from Karoo soil. The system investigated the propagation attenuation over the Karoo soil and vegetation, with great promise. A broad spectrum was measured over a few kilometres and compared to free-space loss. The SE of the berm covered the same spectral bandwidth. In this measurement, scattering effects and knife-edge diffraction were observed.
AFRIKAANSE OPSOMMING: Die werk in hierdie studie dek ’n kragtige tegniek wat gebruik kan word om die voortplanting en die verstrooiingsinligting van elektromagnetiese golwe op ’n voordelige manier af te lei. Dit is voordelig, want tydgebieddata versamel ’n wye spektrum in ’n enkele oordraagbare puls. Tydgebied is in die verlede baie gekritiseer omdat dit ’n dinamiese reikwydte kortkom en dit is nou oorwin deur die direkte steekproefnemingstelsel, RATTY en RTA. Hierdie studie fokus op die ondersoek van ’n tydgebiedmetingssisteem en dit help met die karakterisering van MeerKAT sisteme. Die elementêre komponente van die sisteem bestaan uit ’n vinnig-stygende impulsgenerator wat gekoppel is aan ’n impulsuitstralende-antenna (IRA). Die sisteem is gekalibreer en getoets voordat praktiese metings en toetse in die Karoo uitgevoer kon word. Vir tydgebiedmetings versnel ’n groter bandwydte die metings sonder om die akkuraatheid daarvan te beïnvloed. Die pulsgenerator se fundamentele komponente is ’n stortvloedtransistor en ’n stap-herstel diode (SRD) wat die voorpunt van die puls verskerp. Die eskterne stroombaan rondom hierdie komponente is noodsaaklik en dit bepaal die vorm, amplitude en die stygtyd van die puls. Deur die loop van hierdie ondersoek is die algemene stroombaan rondom die puls verbeter, om die beste moontlike puls vir metings binne in die weerkaatsingskamer en vir metings in die Karoo, te verkry. Na aanleiding van dit is ’n tweede en derde pulsgenerator bron verkry. Vir die metings in die Karoo is ’n puls met ’n groter amplitude vereis om die spektrale inhoud te vermeerder. Dit is noodsaaklik vir elektromagnetiese golf voortplantingsmetings oor afstand asook die beskermings effektiwiteit (SE) van die strukture. Stapel-stortvloed transistors skep pulse met groter amplitudes en dit verbeter die dinamiese reikwydte van die spektrum. ’n Pulsgenerator wat gestapelde stortvloedtransistors insluit is ontwerp, gebou en gemeet om te help met metings in die weerkaatsingskamer en kleinskaal veldmetings in die Karoo. Die derde pulsgenerator is gekoop vir praktiese metings in die Karoo. Die pulsgenerator vervaardig kilovolt pulse met pikosekond stygtye, wat die reikwydte van die spektrum van ons huidige puls uitbrei. Hierdie pulsgenerators vereis ’n antenna vir die uistraling van impulsagtige seine. Die IRA is ’n hoë-wins, groot-bandwydte antenna. Die IRA bestaan uit ’n paraboliese weerkaatser, konieseplaat transmissielyne wat deur weerstande op die skottel getermineer word, asook ’n voedings "balun". Die IRA ontwerp is deeglik bespreek en ’n model is ontwerp, gemeet en verbeter. Die IRA is ook gesimuleer met behulp van ’n rekenaarsagtewareprogram, FEKO. Voordat die tydgebiedsisteem benut kan word, moet dit gekalibreer word en karakteriseringsmetings moet ook daarmee uitgevoer word. Die meetinstrumente wat in hierdie studie gebruik is, is steekproefneming-ossilloskope en direkte steekproefneming-sisteme. Die tekortkominge van elke instrument is ondersoek en bespreek. Die finale meting wat uitgevoer is, dra by tot die werk wat geassosieer word met die SKA. Dit behels antennapatroonkalibrasie, voortplanting van elektromagnetiese golwe oor afstand en die SE van ’n "berm"wat gebou is uit Karoo-grond. Hierdie sisteem is gebruik om die voortplantings-verswakking oor die Karoo-grond en plantegroei te ondersoek en dit lyk baie belowend. ’nWye spektrumis oor ’n paar kilometer gemeet en dit is met wrywinglose ruimte vergelyk. Die SE van die "berm"het dieselfde spektrale bandwydte gedek. In hierdie meting is verstrooiingseffekte en mespunt-diffraksie waargeneem.
Булашенко, Андрій Васильович, Андрей Васильевич Булашенко, and Andrii Vasylovych Bulashenko. "Аналіз антени витікаючої хвилі." Thesis, Сумський державний університет, 2016. http://essuir.sumdu.edu.ua/handle/123456789/47186.
Full textNoor, Azman Nurul Zahirah Binti. "Design of nanostructured polymeric materials for radiation shielding of ionizing radiations." Thesis, Curtin University, 2013. http://hdl.handle.net/20.500.11937/2338.
Full textHaidekker, Andras. "Radiation modelling in complex three dimensional enclosures." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1991. http://theses.uqac.ca.
Full textXiang, Xuwu. "The delta-Sobolev approach for modeling solar spectral irradiance and radiance." Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/25801.
Full text