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Tesis sobre el tema "Radio waves"

Autor: Grafiati
Publicado: 4 de junio de 2021
Última modificación: 25 de julio de 2025

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1

Starck, Patrik. "Energy harvesting of ambient radio waves." Thesis, Uppsala universitet, Avdelningen för datorteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-355020.

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The aim for this thesis was to investigate if harvesting of ambient radio waves could be a viable source of energy and where and when it can be used. A survey of the signal strengths at different locations in Uppsala, Sweden was performed which showed that the cellular frequency bands were the ones that carried the most energy. One circuit was manufactured and two more were simulated, together with the circuitry required to measure and display how much energy that was being harvested. The design was tested at the same locations as the survey of the signal strength was conducted at. The maximum
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2

Hawbaker, Dwayne Allen. "Indoor wide band radio wave propagation measurements and models at 1.3 ghz and 4.0 ghz /." This resource online, 1989. http://scholar.lib.vt.edu/theses/available/etd-08182009-040436/.

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3

Pala, Fatih. "Frequency and polarization diversity simulations for Urban UAV communication and data links." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sep%5FPala.pdf.

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4

Rasam, Setty Harish Raghav. "Assessment of Volumetric Water Content Using Radio Waves." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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Volumetric water content evaluation in structures, substructures, soils, and subsurface in general is a crucial issue in a wide range of applications. The main weakness of subsurface moisture sensing techniques is usually related both to the lack of cost-effectiveness of measurements, and to unsuitable support scales with respect to the extension of the surface to be investigated. In this regard, Wireless Underground Sensor Network are increasingly used non-destructive tool specifically suited for characterization and measurement. It is undeniable that wireless communication technology has bec
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5

Ciavarella, Michele. "Volumetric soil moisture evaluation via radio waves propagation." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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Nowadays technology plays an important role in different sectors of farm management, in particular technologies based on soil moisture assessment have proven to be efficient in helping farmers who need timely techniques to determine crop water requirements. The main weakness of subsurface moisture sensing techniques is usually related both to the lack of cost-effectiveness of measurements and to unsuitable support scales with respect to the extension of the surface to be investigated. In this regard, Wireless Underground Sensor Network are increasingly used non-destructive tool specifically s
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6

Lange, Martin, and Christoph Jacobi. "Analysis of gravity waves from radio occultation measurements." Universitätsbibliothek Leipzig, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-217072.

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In the height range 10–30 km atmospheric gravity waves lead to periodic perturbations of the background temperature field in the order of 2-3 K, that are resolved in temperature profiles derived from radio occultation measurements. Due to the spherical symmetry assumption in the retrieval algorithm and the low horizontal resolution of the measurement damping in the amplitude and phase shift of the waves occurs leading to remarkable errors in the retrieved temperatures. The influence of the geometric wave parameters and the measurement geometry on plane gravity waves in the range 100-1000 km ho
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7

Lange, Martin, and Christoph Jacobi. "Analysis of gravity waves from radio occultation measurements." Wissenschaftliche Mitteilungen des Leipziger Instituts für Meteorologie ; 26 = Meteorologische Arbeiten aus Leipzig ; 7 (2002), S. 101-108, 2002. https://ul.qucosa.de/id/qucosa%3A15225.

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In the height range 10–30 km atmospheric gravity waves lead to periodic perturbations of the background temperature field in the order of 2-3 K, that are resolved in temperature profiles derived from radio occultation measurements. Due to the spherical symmetry assumption in the retrieval algorithm and the low horizontal resolution of the measurement damping in the amplitude and phase shift of the waves occurs leading to remarkable errors in the retrieved temperatures. The influence of the geometric wave parameters and the measurement geometry on plane gravity waves in the range 100-1000 km ho
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8

Thomas, Edwin Christopher. "Phase and amplitude variations in the wave fields of ionospherically reflected radio waves." Thesis, University of Leicester, 1986. http://hdl.handle.net/2381/35807.

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The wavefronts of high frequency (HF) radio waves received after reflection from the ionosphere exhibit both spatial non-linearities and temporal variations which limit the performance of large aperture receiving arrays. The objective of this investigation was to measure the phase and amplitude of ionospherically propagated signals in order to relate these parameters to the reflection process. This thesis describes the design and construction of a large aperture multi-element array and its implementation for wavefrot investigations. The hardware and software developed to control the equipment
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9

Russell, Thomas A. "Predicting microwave diffraction in the shadows of buildings." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10222009-125156/.

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10

Carozzi, Tobia. "Radio waves in the ionosphere : Propagation, generation and detection." Doctoral thesis, Uppsala universitet, Institutionen för astronomi och rymdfysik, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-1184.

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We discuss various topics concerning the propagation, generation, and detec-tionof high-frequency (HF) radio waves in the Earth's ionosphere. With re-gardsto propagation, we derive a full wave Hamiltonian and a polarization evo-lutionequation for electromagnetic waves in a cold, stratified magnetoplasma.With regards to generation, we will be concerned with three experiments con-ducted at the ionosphere- radio wave interaction research facilities at Sura, Rus-siaand Tromsø, Norway. These facilities operate high power HF transmittersthat can inject large amplitude electromagnetic waves into the
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11

Bond, Giles Edward. "The interaction of radio waves with the auroral ionosphere." Thesis, University of Leicester, 1997. http://hdl.handle.net/2381/30629.

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A high power radio wave propagating through the ionosphere perturbs the natural plasma in a number of ways. These include bulk changes in the electron temperature and density, and the excitation of plasma waves and instabilities. The ionosphere can be regarded as a natural plasma laboratory, with far greater scale sizes then anything achievable in a conventional laboratory, thus giving unique access to a range of plasma waves and instabilities. In this thesis results from two campaigns involving the EISCAT (European Incoherent SCATter) ionospheric modification facility (heater) at Tromso, Nort
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12

Carozzi, Tobia D. "Radio waves in the ionosphere : propagation, generation, and detection /." Uppsala : Institutionen för astronomi och rymdfysik, Univ. [distributör], 2000. http://publications.uu.se/theses/99-3364278-2/.

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13

Ellis, Russell Brian. "Linearity of fibre network supported transmission of radio waves." Thesis, Bangor University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389521.

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14

Gåvermark, Erik. "Modeling of Current Drive with Radio Waves on DEMO." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-239380.

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In fusion reactors, one has to make sure that the plasma does not come in contact with the reactor wall. This is done by accelerating electrons within the plasma creating a current. One method to do this is to transmit radio waves into the plasma from antennas which are located in the reactor wall. In this paper, the current current has been studied in a new design of DEMO. In this new design the placement of the antennas is meant to enable a more effective generation of current.A program called FEMIC has been used to create a model of DEMO consisting of plots and data that describes how the r
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15

Hahlin, Axel. "Coupled waves as a model to describe chaotic turbulence pumped by radio waves in the ionosphere." Thesis, Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-356265.

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Experimental results concerning plasma turbulence pumped in theionosphere by powerful radio waves suggest that the turbulence is due todeterministic chaos. To investigate the possibility of deterministic chaosin the ionosphere coupled wave systems have been studied to see chaoticdynamics. If coupled waves can exhibit chaos it is a possible way tomodel ionospheric chaos. The result showed that chaos was present inboth wave systems studied which means that they could possibly explainthe chaos, to verify this more studies needs to be done on theparameters relevant to the coupled wave systems in t
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16

Adaszynski, Wojciech. "Interactive visualization of radio waves propagation in 5G massive MIMO." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254958.

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The complexity of advanced antenna techniques used in the new generation of wireless networks (5G) makes communication between experts and non-technical staff more difficult than ever. As cooperation between network vendors and network operators affects the adoption of the new standard, a need for a new tool has emerged to make technical presentations more engaging and compelling. This thesis presents an exploratory study that aims to examine various design options for an interactive visualization of radiowave propagation to be used by advanced antenna systems experts. Through a Research-orien
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17

Tshisaphungo, Mpho. "Validation of high frequency propagation prediction models over Africa." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1015239.

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The ionosphere is an important factor in high frequency (HF) radio propagation providing an opportunity to study ionospheric variability as well as the space weather conditions under which HF communication can take place. This thesis presents the validation of HF propagation conditions for the Ionospheric Communication Enhanced Profile Analysis and Circuit (ICEPAC) and Advanced Stand Alone Prediction System (ASAPS) models over Africa by comparing predictions with the measured data obtained from the International Beacon Project (IBP). Since these models were not developed using information on t
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18

Smit, Jacobus Petrus. "Theoretical development and implementation of algorithms for the inversion of frequency domain airborne electromagnetic data into a layered earth." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-02222007-142602.

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19

Ding, Ming Sheng. "Modelling and measurement of the scatter of microwaves by buildings." Thesis, University of South Wales, 1994. https://pure.southwales.ac.uk/en/studentthesis/modelling-and-measurement-of-the-scatter-of-microwaves-by-buildings(ab8b0911-5e4f-48ed-882c-d646b5df266f).html.

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The growing usage and demand for microwave communications has led to the increase in system density, particularly in urban areas, and consequently to the increase in the probability of mutual interference between systems sharing the same frequency band. Satellite and point to point microwave communication systems might have to rely on site shielding to reduce the level of this co-channel interference. In urban areas, there is a great possibility of a building obstructing the interference path, thus providing protection. However, there could be more than one interference path. Scattered interfe
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20

Kincaid, Cheryl-Annette Mikler Armin. "Analyzing microwave spectra collected by the solar radio burst locator." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3655.

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21

Stocker, Alan John. "Modification of the ionosphere by means of high power radio waves." Thesis, University of Leicester, 1990. http://hdl.handle.net/2381/35799.

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Experiments have been performed at Troms?, Norway and Arecibo, Puerto Rico to investigate the effects produced by high power radio waves (heating) on the high and low latitude ionospheres, respectively. The modifications induced in the F-region have been observed with both incoherent scatter radars and tow power HF diagnostic radio waves. These observations provide information on both heater-induced large scale changes, and small scale density structures. The spatial and temporal development of the perturbation in electron temperature caused by heating, measured at Troms? for the first time, c
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22

Sim, Chow Yen Desmond. "The propagation of VHF and UHF radio waves over sea paths." Thesis, University of Leicester, 2002. http://hdl.handle.net/2381/7444.

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This thesis is concerned with the statistical studies of VHF/UHF radio wave propagation over the sea path at the limits of line-of-sight range. The objective is to provide a set of data that leads to the understanding of the characteristic of VHF/UHF radio wave over the sea path. A series of experiments were conducted using two paths of around 33 and 48 km across the English Channel. These two paths are between fixed land-based locations that provide an unobstructed condition. This allows a prolonged period of data collection under several sea states and atmospheric conditions without the heav
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23

Vidojevic, Sonja. "Statistics of Langmuir Waves Associated with Type III Solar Radio Bursts." Observatoire de Paris, 2012. https://hal.science/tel-02095131.

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Nous avons examiné les 16 premières années des données ondes et particules par la sonde WIND dans le vent solaire afin de rechercher les évènements de type III in-situ. L'application de critères rigoureux a fourni un ensemble de 36 évènements de grande qualité. Avec un tel ensemble, statistiquement représentatif du phénomène étudié, il est désormais possible de mieux contraindre les modèles de génération de type III. Nous avons étudié les formes précises des distributions de puissance des ondes Langmuir, observées dans le domaine spectral et modélisé ces distributions avec un système de distri
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24

Kurniawan, Teddy. "Analytical methods for near field radio frequency dosimetry for tissue layers and celluar structures." Swinburne Research Bank, 2009. http://hdl.handle.net/1959.3/48743.

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Thesis (PhD) - Faculty of Life and Social Sciences, Swinburne University of Technology, 2009.<br>A thesis submitted in total fulfillment of the requirements for the degree of Doctor of Philosophy, Faculty of Life and Social Science, Swinburne University of Technology - 2009. Typescript. Includes bibliographical references.
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25

Barroso, Mônica Mazzer. "Waves in the forest : radio communication and forest livelihoods in Brazilian Amazonia." Thesis, London School of Economics and Political Science (University of London), 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436117.

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26

Kennett, M. I. "An analysis of the scattering of radio waves within a temperature glacier." Thesis, University of Bristol, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376616.

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27

Kasaba, Yasumasa. "Study of Radio Waves in Geospace via Spacecraft Observations and Numerical Simulations." Kyoto University, 1997. http://hdl.handle.net/2433/154674.

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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである<br>Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(工学)<br>甲第6871号<br>工博第1622号<br>新制||工||1069(附属図書館)<br>UT51-97-H255<br>京都大学大学院工学研究科電子工学専攻<br>(主査)教授 松本 紘, 教授 橋本 弘藏, 教授 津田 敏隆<br>学位規則第4条第1項該当
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28

Munns, David P. D. ""Wizards of the micro-waves" a history of the radio astronomy community /." Available to US Hopkins community, 2002. http://wwwlib.umi.com/dissertations/dlnow/308073.

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29

Nordblad, Erik. "Opening New Radio Windows and Bending Twisted Beams." Doctoral thesis, Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-158797.

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In ground based high frequency (HF) radio pumping experiments, absorption of ordinary (O) mode pump waves energises the ionospheric plasma, producing optical emissions and other effects. Pump-induced or natural kilometre-scale field-aligned density depletions are believed to play a role in self-focussing phenomena such as the magnetic zenith (MZ) effect, i.e., the increased plasma response observed in the direction of Earth's magnetic field. Using ray tracing, we study the propagation of ordinary (O) mode HF radio waves in an ionosphere modified by density depletions, with special attention t
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30

VARGAS, CARLOS EDUARDO ORIHUELA. "ANTENNA PROJECT AND IMPLEMENTATION FOR CHARACTERIZATION OF MOBILE RADIO CHANNEL IN MILLIMETER WAVES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=25606@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO<br>PROGRAMA DE EXCELENCIA ACADEMICA<br>O termo de ondas milimétricas refere-se à porção do espectro eletromagnético com frequências entre 30 e 300 GHz, correspondente a comprimentos de onda de 10 até 1 mm, respectivamente. As características das ondas milimétricas diferem das micro-ondas e das infravermelhas, e são estas diferenças que fazem com que um sistema de ondas milimétricas seja o candidato ideal para algumas apli
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31

Gunashekar, Salil David. "An investigation of the propagation of 2 GHz radio waves over sea paths." Thesis, University of Leicester, 2006. http://hdl.handle.net/2381/30235.

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Three long-range 2 GHz radio paths have been established in the British Channel Islands in order to investigate the characteristics of long-range propagation of UHF radio waves over the sea as part of a project supported by Ofcom, UK. The relationship between specific over-sea propagation mechanisms (such as evaporation ducting and super-refraction) in the lower troposphere and signal strength distribution patterns has been examined, modelled and correlated with meteorological parameters. A number of radio meteorological statistics specifically related to evaporation duct propagation in a temp
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32

Lindeberg, Axel. "Hacking Into Someone’s Home using Radio Waves : Ethical Hacking of Securitas’ Alarm System." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302999.

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The number of IoT systems in our homes has exploded in recent years. By 2025 it is expected that the number of IoT devices will reach 38 billion. Home alarm systems are an IoT product that has increased dramatically in number and complexity in recent years. Besides triggering an alarm when an intruder tries to break in, a modern system can now control your light bulbs, lock and unlock your front door remotely, and interact with your smart speaker. They are undeniably effective in deterring physical intrusion. However, given the recent rise in complexity how well do they hold up against cyber a
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33

Ehn, Jonas. "Propagation of Radio Waves in a Realistic Environment using a Parabolic Equation Approach." Thesis, Linköpings universitet, Teoretisk Fysik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-157610.

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Radars are used for range estimation of distant objects. They operate on the principle of sending electromagnetic pulses that are reflected off a target. This leads to the propagation of electromagnetic waves over large distances. As the waves propagate, they are affected by several aspects that decrease the performance of the radar system. In this master thesis, we derive a mathematical model that describes electromagnetic propagation in the troposphere. The model developed is based on a parabolic equation and uses the split-step Fourier method for its numerical solution. Using the model, we
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34

Monaghan, William D. "Experimental studies of electromagnetic signals to enhance radio imaging method (RIM)." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5422.

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Thesis (M.S)--West Virginia University, 2007.<br>Title from document title page. Document formatted into pages; contains xi, 104 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 69-70).
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35

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

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Thesis (M.S. in Meteorology)--Naval Postgraduate School, March 2010.<br>Thesis Advisor(s): Guest, Peter S. ; Goroch, Andreas K. "March 2010." Author(s) subject terms: Electromagnetic propagation, electromagnetic scattering, groundwave propagation, mathematical techniques, variance reduction. Includes bibliographical references (p. 67-68). Also available in print.
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36

Brown, Martin. "High voltage soliton production in nonlinear transmission lines and other pulsed power applications." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364003.

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37

Babcock, Bruce Kevin. "Electronic communications systems and the frequency domain an illustrated primer for C3 student /." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA236936.

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Thesis (M.S. in Systems Technology)--Naval Postgraduate School, June 1990.<br>Thesis Advisor(s): Weir, Maurice D. Second Reader: Schwendtner, Thomas A. "June 1990." Description based on title screen as viewed on October 16, 2009. DTIC Descriptor(s): Frequency, integrated systems, high rate, students, electronic equipment, transmittance, spectra, pulses, graphics, attenuation, communication and radio systems, width, noise, data rate, vocabulary, bandwidth, modulation, multiplexing, radio transmission, radio waves, transmitting, fourier DTIC Indicator(s): Command control and communications, radi
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38

Martínez-Sansigre, Alejo. "Distant obscured quasars." Thesis, University of Oxford, 2006. http://ora.ox.ac.uk/objects/uuid:a764a410-4464-4b92-831d-34e8a383d78f.

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This thesis presents a study of high-redshift obscured (type-2) quasars, selected at mid-infrared and radio wavelengths. This population had remained elusive, even to hard X-ray surveys, and in Chapter 2 I compare the selection of type-2 quasars in X-ray and mid-infrared surveys, as well as explaining the criteria I will use to search for these objects at z ~ 2, around the peak in the unobscured (type-1) quasar activity. Chapter 3, presents a sample of radio-intermediate type-2 quasars selected from the criteria de- scribed in Chapter 2. Optical spectroscopy shows indeed that at least half of
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39

Fan, Shu-Hao. "Convergence of millimeter-wave and photonic interconnect systems for very-high-throughput digital communication applications." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42888.

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In the past, radio-frequency signals were commonly used for low-speed wireless electronic systems, and optical signals were used for multi-gigabit wired communication systems. However, as the emergence of new millimeter-wave technology introduces multi-gigabit transmission over a wireless radio-frequency channel, the borderline between radio-frequency and optical systems becomes blurred. As a result, there come ample opportunities to design and develop next-generation broadband systems to combine the advantages of these two technologies to overcome inherent limitations of various broadband end
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40

Ahmad, Saad. "Modeling the Discharge Loading of Radio Frequency Excited CO2 Slab lasers." Digital WPI, 2011. https://digitalcommons.wpi.edu/etd-theses/1081.

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"RF excited CO2 lasers are widely used in industry. They provide relatively high power discharge levels while maintaining compactness, simplicity, and durability with respect to other competing laser technologies. To attain high power levels in the range of 5-10 KW, lasers with large electrode areas have to be designed. Unfortunately, due to the large electrode length requirements, transmission line effects make the discharge loading nonlinear, adversely affecting the efficiency of the CO2 laser. A standard approach to linearize the discharge loading is to introduce shunt inductors across the
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41

Bignall, Hayley Emma. "Radio variability and interstellar scintillation of blazars." [Adelaide : H.E. Bignall, 2003. http://web4.library.adelaide.edu.au/theses/09PH/09phb5931.pdf.

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Bibliography: leaves 191-202. 1. Introduction -- 2. Instrumentation and calibration -- 3. A radio monitoring program for southern blazars -- 4. Analysis of long-term blazar radio variability -- 5. Probing microarcsecond-scale structure using interstellar scintillation -- 6. The rapid scintillator, PKS 1257-326 -- 7. Conclusions and scope for further work.
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42

Channamallu, Aditya. "Software Defined Radio Based Modulated Scatterer Antenna Measurement." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4447.

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The modulated scattering technique is used in conjunction with a Software Defined Radio (SDR) dongle to obtain a software-based modulated signal output. SDR# is the software package used to get spectrum analysis of the modulated signal. A transmitter yagi antenna sends a 2.304GHz signal on to an antenna connected to a reflector coefficient modulator (700Hz) and the modulated waves are received by another yagi. The receiver yagi antenna is then connected to a frequency converter to convert a 2.304GHz signal to a 144MHz dongle input signal which finally puts the scattered output on computer soft
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43

Löfås, Henrik. "Ionospheric modification by powerful HF-waves : Underdense F-region heating by X-Mode." Thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-121898.

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Observations of modifications of the electron temperature in the F-region produced by powerful high-frequency waves transmitted in X-mode are presented. The experiments were performed during quiet nighttime conditions with low ionospheric densities so no reflections occurred. Nevertheless temperature enhancements of the order of 300-400K were obtained. The modifications found can be well described by the theory of Ohmic heating by the pump wave and both temporal and spatial changes are reproduced.  A brief overview of several different experimental campaigns at EISCAT facilities in the period
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Hawbaker, Dwayne Allen. "Indoor wide band radio wave propagation measurements and models at 1.3 ghz and 4.0 ghz." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/44287.

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An extensive radio wave propagation measurement campaign was conducted at 1.3 GHz and 4.0 GHz inside four buildings, including a sports arena, a modern closed-plan office building, and two dissimilar, open-plan factories. Measurements were recorded at 57 locations using base station antenna heights of 1.7 meters and 4.0 meters. Results were obtained for mean and maximum excess delay, rms delay spread, time delay jitter, differential delay jitter, and path loss through analyses of impulse response estimates, which were obtained via repetitive 5 ns probing pulses. The effects of frequency, anten
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45

Pecoraro, Michael A. "Characterization of the effects of the human head on communication with implanted antennas /." Online version of thesis, 2010. http://hdl.handle.net/1850/11698.

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46

Kincaid, Cheryl-Annette. "Analyzing Microwave Spectra Collected by the Solar Radio Burst Locator." Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3655/.

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Modern communication systems rely heavily upon microwave, radio, and other electromagnetic frequency bands as a means of providing wireless communication links. Although convenient, wireless communication is susceptible to electromagnetic interference. Solar activity causes both direct interference through electromagnetic radiation as well as indirect interference caused by charged particles interacting with Earth's magnetic field. The Solar Radio Burst Locator (SRBL) is a United States Air Force radio telescope designed to detect and locate solar microwave bursts as they occur on the Sun. By
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47

Цопа, А. И., В. К. Иванов, В. И. Леонидов, et al. "The research Program of millimetric Radio waves attenuation characteristics on perspective communication lines of Ukraine." Thesis, Proc. of XIII International Conf. Modern problems of Radio Engineering, Telecommunications and Computer Science /TCSET’2016/. – Lviv-Slavsko, 2016. – P. 638-642, 2016. http://openarchive.nure.ua/handle/document/3555.

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48

Krupař, Vratislav. "Stereoscopic Observations of Solar Radio Emissions by the S/Waves Instrument onboard the STEREO Spacecraft." Observatoire de Paris, 2012. https://hal.science/tel-02095132.

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Cette thèse est principalement consacrée à une étude des sursauts radio type III observés par l'instrument S/Waves à bord du satellite Solar TErrestrial RElations Observatory (STEREO). Ces émissions sont produites lors de période d'activité solaire accrue par des faisceaux d'électrons suprathermiques s'échappant de la couronne solaire le long de lignes de champ magnétique ouvertes. Lorsque des électrons rapides se propagent dans le milieu interplanétaire (IP), des ondes de Langmuir sont générées à la fréquence plasma locale des électrons fpe par une instabilité dite "bump-on-tail". Ces instabi
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Harding, James. "3D Simulation of the Quasilinear Electron-Langmuir Wave Interaction in Type III Solar Radio Bursts." Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/23289.

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This thesis presents a three-dimensional relativistically correct model of the electron beam-Langmuir wave interaction in the solar corona, as well as a model of the radial electron density profile of the ambient solar plasma through which an electron beam passes. 1D models of the beam/plasma interaction have long been used, as have empirical fits for the electron density profile. In support of the overall goal of this thesis, to develop a more realistic understanding of the plasma physics processes underlying Type III solar radio bursts, we first present strong evidence for a new and physical
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Knotts, Michael E. "Experimental studies of multiple scattering by rough surfaces." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/30269.

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