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Benomar, Ahmed. "Etude des Antennes à Résonateurs Diélectriques. : Application aux Réseaux de Télécommunications". Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0025/document.
Pełny tekst źródłaA fast technological development in the telecommunications domain, as mobile telephony, wireless networks, TV over Satellite, Radar Applications (civil or military)…etc, is observed. This considerable growth has led to enormous needs and caused a major technological evolution in antennas. These have to face different needs such as gain improvement, bandwidth enlargement, and different existing problems, such as cost and overcrowding…etc. Though, our goal is to design antenna topologies that are simple, having Low overcrowding and relatively with high gain operating in multiband and/or ultra large. To achieve this we headed to Dielectric Resonator Antennas (DRA) in UHF and SHF bands. Recently they have been the subject of several studies and have gained great interest from both academic and industrial sectors. Due to their diverse and simple geometries, they can be fed with different usual techniques. Furthermore, they can be smaller than patch antennas. The first part of this work has focused on the study of cylindrical DRAs, and then a validation of the simulating tool has been done after comparison with measurement results. For a multi-standard utilization, enlargement antennas’ operating bands, to have bi-band behaviour, get a modification of the resonant frequency and also a reduction of the overcrowding, the second part is dedicated to the study of new resonator topologies based on a vertical and radial stack of two cylinders, and then a multilayer and ring topologies. The obtained results found their applications in GSM900-DCS1800-UMTS-WiFi…
Mello, Rafael Gonçalves Licursi de. "Active and passive metasurfaces : methodology for the design of a low profile, beam-steerable, multiband, and wideband antenna". Electronic Thesis or Diss., Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAT025.
Pełny tekst źródłaMetasurfaces are artificial engineered materials that can be combined with traditional microwave components in ground-breaking solutions. The research on the use of metasurfaces in the roles of antenna reflector and/or superstrate considerably increased mainly from the beginning of the 2020s, because of their innovative functionalities in line with the ultimate Telecommunication trends. In this thesis, methodologies for the use of passive and active metasurfaces in the design of antennas are presented. A first methodology which exploits both the near-perfect electric conductor (PEC) and near-perfect magnetic conductor (PMC) behaviors of a dual-band artificial magnetic conductor (AMC) is used to design a low-profile, multiband, directive antenna. This methodology is validated with a prototype suitable for the European standards of 4G/5G and Wi-Fi 2.4/5/6E, operating within the following bands: 2.40–2.70 GHz, 3.40–3.80 GHz, 5.17–5.83 GHz, and 5.93–6.45 GHz. Additionally, a methodology to handle the Fabry-Pérot mechanism in an antenna composed of a grooved rounded-edge bow-tie, a passive dual-band AMC, and an active multiband Huygens metasurface is presented. This methodology is validated with the design of a multiband, directive, low-profile, antenna that performs an independent beam-steering in only one of the operating frequency bands. Through the controlling of the bias voltages over four columns of varactors in the reconfigurable, multiband Huygens metasurface, the beam may be dynamically steered in ±51°, in a continuous manner, in a frequency range lying inside the European 5G frequency range (from 3.50 to 3.65 GHz. All at once, the radiation patterns concerning the 4G and Wi-Fi 2.4/5/6E keep practically unaffected
Jebbawi, Khodor. "Etude et réalisation d'un système embarqué UHF appliqué à la récupération de statistiques chez le sportif amateur". Electronic Thesis or Diss., Aix-Marseille, 2020. http://theses.univ-amu.fr.lama.univ-amu.fr/200917_JEBBAWI_711xpp867owr742fklcav366xhj_TH.pdf.
Pełny tekst źródłaThis thesis was funded by the ANRT. The main goal is to design a specific antennas for connected objects. The final application is dedicated for the sport, in order to collect the performance of an amateur football player by using a connected ball and a connected strap. This device is based on the passive RFID. The system is composite of: a wearable antenna placed on the ankle, able to communicate with RFID tags inserted inside the ball. At the end of the match, the statistics collected by the sensors are sent by using BLE connection to a totem in order to display them. Two main objectives are targeted in this thesis: the first one is designing a broadband and multistandard antennas for readers, able to minimize the influence of the human body without sacrificing reading distance, the second objective is designing a resistant antennas for RFID tags
Moustafa, Lina. "Conception d'antennes à Bande Interdite Electromagnétique large bande et multibandes à base de métasurfaces". Limoges, 2009. https://aurore.unilim.fr/theses/nxfile/default/0b6d599a-f2a9-4deb-b823-5dba8a5d5130/blobholder:0/2009LIMO4027.pdf.
Pełny tekst źródłaThis PhD thesis is dedicated to the study of Electromagnetic Band Gap antennas based on metasurfaces. Metasurfaces are employed in the antenna design to correct the usual limitations of the technology and more precisely to enlarge the banwidth. The possibilities offered by combining partially reflecting surfaces, with respect to structure height are explored. Multi-band and broadband EBG antennas with structured interface are designed. An experimental validation of the wideband antenna concept based on metasurfaces is realized. Finally, it is demonstrated that the product gain-bandwidth of such an antenna can be further improved by the use of a multiple feeding sources system
Letestu, Yoann. "Etude des antennes hélices quadrifilaires imprimées larges bandes et multibandes - Application en bande Ku. ; Contribution à l'étude générale du couplage mutuel". Rennes 1, 2004. http://www.theses.fr/2004REN10163.
Pełny tekst źródłaHuitema, Laure. "Conception d’antennes miniatures à base de matériaux innovants pour systèmes de communications mobiles". Limoges, 2011. https://aurore.unilim.fr/theses/nxfile/default/a25b0fa1-3acc-4afb-ad61-8ca9e1c81d3f/blobholder:0/2011LIMO4031.pdf.
Pełny tekst źródłaGiven the desire to integrate a large number of new services in last generation of mobile handheld devices and in order to drastically decrease their dimensions, new concepts of smart antennas are being considered. The main objective is to offer new services in a trendy mobile handheld with an optimal quality and an improved link budget. The antenna has to be small and in order to improve the reliability of wireless links, the antenna structure must have a frequency tunability, a reconfigurable polarization or radiation pattern. In order to satisfy these objectives, this manuscript focuses on two axes. At first, it is necessary to unlock the constraints on the miniaturization of such antennas to multiple services by studying the potentialities and effectiveness of original materials dedicated to the compliance and optimization of the antenna performances within its environment. Thanks to this study, it is then possible to investigate new concepts of reconfigurable antennas to optimize their performances within their environment. This manuscript is proposing answers to these challenges by detailing the development, the conception and the manufacturing of four different miniature and reconfigurable antenna designs using new kind of materials
Oudin, Marc. "Etude d'algorithmes de traitement d'antenne sur signaux large bande et signaux radar bande étroite à antenne tournante". Paris 6, 2008. http://www.theses.fr/2008PA066209.
Pełny tekst źródłaLardies, Joseph. "Etude d'antennes acoustiques a directivite constante sur une large bande". Toulouse 3, 1987. http://www.theses.fr/1987TOU30214.
Pełny tekst źródłaZemmour, Hamadache. "Réseaux de capteurs sans fil enfouis ultra large bande : antenne et liens radios". Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1076/document.
Pełny tekst źródłaWireless underground sensor networks (WUSN) consist of sensors which are buried in a medium with their antennas, in particular in soil. They attract a huge interest in different fields, like environment monitoring, precise agriculture, navigation and security. The existing narrowband systems operate at frequencies below 1 GHz. These systems imply the use of cumbersome antennas, which complicates the deployment and increases its cost. Furthermore, the use of narrow bandwidths limits the possible communication data rates and the potential resolution in localization applications. Finally, current systems are very energy consuming, which limits the lifetime of the underground elements.To overcome these drawbacks for certain applications of WUSN, we propose in this thesis the use of ultra wideband technology (UWB), in the normalized band 3.1 - 10.6 GHz, in WUSN. This technique allows the use of compact antennas, simplifying deployment, improving the localization accuracy and increasing communication data rates and the lifetime of the underground sensors.In order to assess the feasibility study of UWB WUSN, we have designed and realized three compact UWB antennas and analyzed the effect of soil on the performances of these underground UWB antennas and on the underground UWB communication links. Compared with operating in free space, burying the antenna shifts the antenna bandwidth towards low frequencies. This shift increases with soil water content. The attenuation introduced by the buried UWB channel, increases with the operating frequency, the burial depth and the soil moisture. However, we have shown that reliable communications are possible for distances of propagation in soil smaller than 30 cm and soil water contents below 20%
Decroze, Cyril Nicolas. "Etude et optimisation d'un nouveau type d'antenne coplanaire : Application à des liaisons de proximité et utilisation pour des dispositifs multifonctions et large bande". Limoges, 2002. http://www.theses.fr/2002LIMO0032.
Pełny tekst źródłaThis report presents the study of a new type of coplanar antenna : "the coplanar wire patch antenna". The uniplanar topology of this radiating element, as well as its low frequency working mode, makes it a very compact structure which allows to answer the current needs of compact antennas for the modern telecommunications. Various developments based on this original concept are proposed, to expand the intrinsic performances of the antenna towards wide band and multifunction radiating devices. On the other hand, the coplanar wire-patch antenna is used to be directly integrated into a communication module dedicated to wireless metering of energy resources. This work also presents the technological solutions considered to directly print the aerial on the case of the communication module, as well as the size constraints which the integrated antenna should answer in this particular context
Goncalves, Daniel. "Traitement d'antenne et matrice spectrale large bande". Grenoble INPG, 1999. http://www.theses.fr/1999INPG0055.
Pełny tekst źródłaBories, Serge. "Conception et analyse des performances d'antennes pour les communications ultra large bande". Phd thesis, Paris 11, 2006. http://pastel.archives-ouvertes.fr/pastel-00002430.
Pełny tekst źródłaHarrabi, Amal. "Conception et réalisation d'une antenne plate pour la réception satellite". Nantes, 2015. http://archive.bu.univ-nantes.fr/pollux/show.action?id=0257079a-bfac-4b59-9cf7-c5a0e1f93a8f.
Pełny tekst źródłaDespite the development of terrestrial links, satellite communication is remaining an interesting mean of information transmission. Broadcasting, pay-TV operators, video, data and broadband Internet services are provided by satellites in a trustworthy way. An important component for the satellite communication, other than the satellite itself, is the receiving antennas deployed all over the world with a huge number. The most popular one is the parabola but this structure does not meet any longer the new aesthetics and the additional functional requirements. For this purpose, motivated researchers worldwide are working on presenting new discreet and self-steering receivers. Indeed, new structures that allow automatic beam steering are beginning to merge into the market but with relatively high prices. We aim with the present work to design a flat antenna array with electronically beam scanning at an affordable price. Therefore, an alternative broadband receiving antenna is designed and implemented for TV channels reception in Ku-band. It consists of an antenna array of 256 radiating elements. The radiating element of an original shape is designed using a methodological approach based on printed antenna theory and simulations. A bandwidth of over 2 GHz (10. 7 – 12. 7 GHz) is obtained from this printed element with a footprint of less than the wavelength. With a suitable array configuration, a directivity of about 30 dBi is achieved, good enough for geostationary satellite signal reception
Lorho, Nina. "Etude et conception d'une antenne compacte ultra large bande à diversité de polarisation : application à la radiogoniométrie". Thesis, Nantes, 2017. http://www.theses.fr/2017NANT4062/document.
Pełny tekst źródłaRadio direction finding (DF) allows for the measurement of the direction of arrival of incoming electromagnetic signals. Its main applications include spectrum monitoring and electronic warfare. DF antennas and arrays are subject to new problematics (bandwidth, compactness and polarization diversity) while DF algorithms have kept on improving. Previous works have initiated the design of such antennas and arrays. This work aims at designing an antenna with reduced dimensions for the VHF and UHF frequency bands and with a polarization diversity. This antenna shall then be integrated in a functional DF array. For this purpose, a planar antenna has been designed and measured in the 500-3000 MHz frequency band. Its final dimensions are 150mm x 150mm (λ/4 x λ/4). This antenna has then been integrated in the final DF array whose accuracy on the same frequency band is of the order of 2° for a final size of 260mm (diameter) x 150mm (height), that is λ/2,3 x λ/4. This study has also allowed for the design of a low-profile absorber (with a height of 25mm, that is λ/24 at its lowest frequency of operation). An increase of 10dB in the front to back ratio of the proposed antenna has been enabled by this absorber on its whole frequency band
Gaha, Hafedh. "Analyse et Conception des Antennes Fractales : applications aux Télécommunications Large Bande". Phd thesis, Toulouse, INPT, 2007. http://oatao.univ-toulouse.fr/7570/1/gaha.pdf.
Pełny tekst źródłaChauvet, François. "Réseau d'antenne conforme, phasé, large bande et bipolarisé pour applications radar UHF sur dirigeable". Paris 6, 2008. http://www.theses.fr/2008PA066024.
Pełny tekst źródłaLévêque, Hervé. "Détection et localisation de sources large bande par des réseaux d'antennes". Toulouse, ENSAE, 1996. http://www.theses.fr/1996ESAE0023.
Pełny tekst źródłaBahram, Mohamed. "Analyse d'une antenne plaque du type doublet replie a tres large bande a l'aide des methodes aux differences finies et des moments : applications aux reseaux a tres large bande". Rennes 1, 1988. http://www.theses.fr/1988REN10041.
Pełny tekst źródłaBahram, Mohamed. "Analyse d'une antenne plaque du type doublet replié à très large bande à l'aide des méthodes aux différences finies et des moments application aux réseaux à très large bande /". Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376115099.
Pełny tekst źródłaLEMAN, PASCAL. "Modelisation et simulation des instrumentations complexes a architectures materielle et logicielle. Conception de l'electronique associee a une antenne acoustique large bande". Toulouse 3, 1999. http://www.theses.fr/1999TOU30096.
Pełny tekst źródłaCheype, Cyril. "Etude et utilisation des propriétés des matériaux BIPs à défaut pour la conception d'antennes". Limoges, 2001. http://www.theses.fr/2001LIMO0017.
Pełny tekst źródłaSincie few years, the Photonic Band Gap structure study is in considerable extension. Numerous applications has been made in optical frequencies as well as in microwave frequency range for the design of filter or antenna devices. This report presents a description of the electromagnetic characteristics of the Photonic Band Gap materials. We particularly focus on the PBG materials with defects
Delestre, Cyrile. "Géolocalisation d'émetteurs en une étape : Algorithmes et performances". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLN006/document.
Pełny tekst źródłaThe context of the thesis is the transmitters geolocalization (position estimation in the space) of radiocommunication from several widely spaced multi-sensor stations. The conventional geolocalization methods as the tirnagulation are in 2 staps (the first step estimates intermediate parameters and the second step "merges" these mesures from the stations in order to obtain the transmitters positions). The 1 stap methods use the observertions from all the stations to directly and optimally estimate the sources positions. Directly handling the signals on the global array (composed of all the local stations) leads to a broadband effect on the signals between the stations.The thesis proposes to study the residual broadband effect on the global array of the 1 step methods. Then we propose improvements on some 1 step geolocalization methods, especially based on the random matrix theory in large dimension and on the introduction of a new method named LOST-FIND. Finally, a new approach differently tackling the braodband problem has been introduced and leads to TARGET algorithm
Yousuf, Muhammad Amir. "Modélisation paramétrique des petits terminaux et antennes multi-bandes ou ultra large bande". Phd thesis, Télécom ParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00634866.
Pełny tekst źródłaHarck, Alexandre. "Conception et validation de déphaseurs large bande intégrant des MEMS-RF dans un environnement hostile". Thesis, Limoges, 2014. http://www.theses.fr/2014LIMO0044/document.
Pełny tekst źródłaThese research works is within the context of an improved link budget telemetry data on space launchers. For this device, an electronically steerable antenna was chosen. It uses an array of four patch antennas supplied by a prototype composed of a power splitter 1 to 4 and four phase shifters. For each selected phase shifters, the phase states are 0 °, 90 ° and 180 °.After a bibliographical study, the best phase shifters that can perform this function are the shifters based on hybrid coupler. Thanks to the use of RF-MEMS in these circuits, it is not necessary to add power amplifiers because these components are linear and present low RF losses. Several topologies of phase shifters based on hybrid coupler using RF-MEMS were studied. According to this study, it was possible to reduce the size of circuits without damaging the RF performance, which allowed us to choose two of them. A remote control is needed for these devices to relay box then was chosen for this role. The first prototype consists of a power divider which was commissioned and produced phase shifters. The second prototype is fully integrated on-chip, which has reduced the device surface and improves the RF losses.These studies were able to demonstrate the feasibility to produce a simple linear prototype with low RF losses
Sérier, Cédric. "Conception, réalisation et caractérisation d'antenne à bande interdite photonique : application au fort gain". Limoges, 2002. http://www.theses.fr/2002LIMO0017.
Pełny tekst źródłaThis report is a study on photonic crystals, in order to use their properties to ceate P. B. G. Resonator antennas : Wideband 1D P. B. G. Resonator antenna : High gain 1D P. B. G. Resonator antenna : 3D P. B. G. Resonator antenna. More precisely, the different steps to design such antennas are presented as well as a study on the excitation of the structure by slot, which can replace patch antenna excitation
Vitale, Quentin. "Modélisation et conception d'antennes radar large bande pour la cartographie de la teneur en eau volumique des sols agricoles". Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066189/document.
Pełny tekst źródłaThe research work submitted in this PhD dissertation is part of research project which aims to develop a new tool for mapping the soil water content in agricultural context with ground penetrating radar technology. The scope of this particular work is the development of two prototypes of wideband radar antennae. Hence, two prototypes of antennae have been numerically designed based on a 3D finite-difference in time-domain (FDTD) electromagnetic solver of Maxwell's equations. The guiding principles that have been followed during the design are mainly a small size antenna (A4 format) and achieving the wider bandwidth possible in the frequency range 100 MHz - 1 GHz (in the air). In order to study the behavior of our prototypes when put in presence of soils, we conducted a numerical study representing the soils by half-spaces. This numerical study was based on the analysis of the antennae reflection coefficient in the frequency domain (or return loss coefficient s11). To be as close as possible to field conditions, the effect of a non ideal contact between the antenna and the soil (represented by a small elevation of the antenna) as well as the effect of soil surface rugosity (represented by corrugated iron-like and eggbox-like surface) have been investigated. Based on this numerical study, two prototypes of antennae (one bow-tie-like and on elliptical dipole) have been physically built and tested in both lab and field conditions. The test in lab condition enabled us to: (i) check the similarity between measured s11 in a controlled environment and corresponding FDTD simulation of the antenna including all antenna parts, (ii) calibrate the antenna in both far field and near field conditions which enabled the use of an analytical model to simulated the antenna s11 in presence of soil, (iii) estimate the dielectric permittivity of a sand sample using both FDTD and analytical simulations. Finally, the prototypes were tested in field condition in order to verify their behavior for in situ measurements. These tests show that using unshielded coaxial cable has a very important impact on the data (noise) and that the prototypes demonstrate a good sensitivity to dielectric permittivity contrasts
Ripoche, Olivier. "Miniaturisation d'antennes en bande VHF pour applications spatiales". Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2013. http://tel.archives-ouvertes.fr/tel-00938676.
Pełny tekst źródłaDesrumaux, Laurent. "Contribution à la conception de sources de rayonnement Ultra Large Bande appliquées à l'imagerie Radar et aux rayonnements forte puissance". Limoges, 2011. https://aurore.unilim.fr/theses/nxfile/default/30fa4b9e-60bc-4c6f-9b0e-810914356a83/blobholder:0/2011LIMO4034.pdf.
Pełny tekst źródłaThis document presents the design and the realization of a miniature Ultra Wide Band antenna, dedicated to the radiation of very short pulses in the frequency band [800MHz - 8GHz]. From experimental performances, the association of this antenna with an optoelectronic device, assuring the best synchronization possible between different sources, has lead to the evaluation of the performances of a global system including as many generators as antennas (evaluation of the necessary antenna number in the array to radiate a power density of 1W/cm² at a distance of 1km as function of the peak level of the feeding pulses). Previously dedicated to electronic warfare applications, this antenna has also been used for imaging Radar applications. It has been the starting point in the development of a novel autonomous and ultrafast Radar system, consisting in radiating pulses in different directions successively along time, azimuth per azimuth. This development has been made possible thanks to the use of a particular optoelectronic device, based on the creation of asynchronous optical pulses trains with different repetition rates. Finally, in order to obtain an electromagnetic image of the analyzed scene with this principle, two imaging algorithms have been developed, each of them being associated with a particular reception configuration. These algorithms have been compared with the time reversal method and the back projection algorithm, in association with a SAR imaging system
Manac'h, Lilia. "Conception et réalisation d'antennes en matériaux composites : intégration dans des plates-formes". Thesis, Rennes 1, 2013. http://www.theses.fr/2013REN1S079.
Pełny tekst źródłaThe technical and operational requirements of naval, terrestrial and aerial vehicles lead to the design and installation of a great number of antennas for communications. At the same time, composite materials have been used for many decades in structural panels of vehicles for their intrinsic qualities (lightness, high mechanical performance, insensitivity to corrosion ...). The purpose of this manuscript is the study and engineering of composite materials for antenna applications at microwaves. After an exhaustive survey of the dielectric characteristics of the various elements of composite materials, dielectric characterization of composite materials manufactured in the Laboratory was carried out using two different methods in two different frequency bands. Meanwhile, an analysis of their conductive characteristics allows carbon-fiber tissues to be used in the design of radiating elements. First, two "full-composite" square shaped antennas based on carbon-fiber tissues, glass-fiber tissues and polyester or epoxy resin have been developed, fabricated and measured. Their performance, similar to that of reference metal antennas demonstrates their relevance for microwave applications. Then, three different topologies of ultra wideband "full-composite" antennas have been specifically developed for the SAMCOM (/Antenna Systems in COMposite Materials)/ FUI project. The first, a Rugby-Ball shaped antenna, has one octave and a half of bandwidth with a positive gain and λ/4 x λ/4 x λ/10 dimensions (length x width x height). The second, a 3D dipole antenna with λ/3 x λ/3 x λ/10 dimensions, has two octaves and a half of bandwidth also with a positive gain. At last, the third antenna with a planar structure has been specifically developed for the reception of digital terrestrial television (DTT) and will be, at the end, integrated into a structural panel of a terrestrial vehicle
Chami, A. "Miniaturisation et intégration d'antennes imprimées pour systèmes communicants ULB pulsés". Phd thesis, Université de Nice Sophia-Antipolis, 2011. http://tel.archives-ouvertes.fr/tel-00668605.
Pełny tekst źródłaLepage, Anne Claire. "Analyse et optimisation d'antennes tridimensionnelles : applications à la conception d'antennes compactes intégrées dans un système de communication ultra-large bande". Phd thesis, Télécom ParisTech, 2005. http://pastel.archives-ouvertes.fr/pastel-00002238.
Pełny tekst źródłaVitale, Quentin. "Modélisation et conception d'antennes radar large bande pour la cartographie de la teneur en eau volumique des sols agricoles". Electronic Thesis or Diss., Paris 6, 2014. http://www.theses.fr/2014PA066189.
Pełny tekst źródłaThe research work submitted in this PhD dissertation is part of research project which aims to develop a new tool for mapping the soil water content in agricultural context with ground penetrating radar technology. The scope of this particular work is the development of two prototypes of wideband radar antennae. Hence, two prototypes of antennae have been numerically designed based on a 3D finite-difference in time-domain (FDTD) electromagnetic solver of Maxwell's equations. The guiding principles that have been followed during the design are mainly a small size antenna (A4 format) and achieving the wider bandwidth possible in the frequency range 100 MHz - 1 GHz (in the air). In order to study the behavior of our prototypes when put in presence of soils, we conducted a numerical study representing the soils by half-spaces. This numerical study was based on the analysis of the antennae reflection coefficient in the frequency domain (or return loss coefficient s11). To be as close as possible to field conditions, the effect of a non ideal contact between the antenna and the soil (represented by a small elevation of the antenna) as well as the effect of soil surface rugosity (represented by corrugated iron-like and eggbox-like surface) have been investigated. Based on this numerical study, two prototypes of antennae (one bow-tie-like and on elliptical dipole) have been physically built and tested in both lab and field conditions. The test in lab condition enabled us to: (i) check the similarity between measured s11 in a controlled environment and corresponding FDTD simulation of the antenna including all antenna parts, (ii) calibrate the antenna in both far field and near field conditions which enabled the use of an analytical model to simulated the antenna s11 in presence of soil, (iii) estimate the dielectric permittivity of a sand sample using both FDTD and analytical simulations. Finally, the prototypes were tested in field condition in order to verify their behavior for in situ measurements. These tests show that using unshielded coaxial cable has a very important impact on the data (noise) and that the prototypes demonstrate a good sensitivity to dielectric permittivity contrasts
Nachabe, Nour. "Évaluation des technologies d'impression 3D pour le développement d'antennes directives à large bande passante pour les liaisons backhaul en bandes millimétriques V et E". Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4118/document.
Pełny tekst źródłaIn order to address the ever-increasing demand of higher data rates, adding small cells to the existing macrocells infrastructure is one of the most important milestones of the 5G roadmap. With the integration of small cells and the re-organization of the network topology, backhaul bottleneck is the main challenge to address in the near future. Facing the costs of deployments of fiber optic connections, point-to-point wireless backhaul links using millimeter wave (mmW) frequencies are gaining prominence. 5G future frequencies, to be discussed under the World Radiocommunication Conference 2019 (WRC-19) open-up the way towards mmW frequency band where large bandwidths are naturally available. The high bandwidths available at these frequencies enable several Gbps data rate backhaul links, which is un utmost necessity to respect the 100 Mbps user-experienced data rate promised by the 5G standard. Millimeter-wave frequencies in V and E-bands unlicensed/light licensed spectrum are considered as primary candidates for backhaul links. In addition to the light license regime, the high free space path loss experienced at these frequencies is rather beneficial to limit the interference between small cells links. Moreover, the high available bandwidths at V and E-bands enable to achieve multi Gb/s links without using complex modulation schemes. In this thesis, we focused our research study on developing high gain wide-band antennas usable in point-to-point backhaul links in a Line of Sight (LoS) context. Leveraging cost-efficient technologies like 3D printing and Printed Circuit Board (PCB) on FR4 substrates, we studied two high-gain antenna types: lens antennas and flat array antennas
Pecquois, Romain. "Etude et réalisation d’une source de rayonnement large bande de forte puissance basée sur un concept innovant de transformateur résonant impulsionnel". Thesis, Pau, 2012. http://www.theses.fr/2012PAUU3047/document.
Pełny tekst źródłaNowadays, a broad range of modern defense applications requires compact pulsed power generators to produce high-power electromagnetic waves. In a conventional design, such generators consist of a primary energy source and an antenna, separated by a power-amplification system, such as a Marx generator or a Tesla transformer, which forwards the energy from the source to the antenna. The present system, however, uses a novel and very compact high-voltage resonant pulsed transformer to drive a dipole antenna. The complete pulsed power source, termed MOUNA (French acronym for “Module Oscillant Utilisant une Nouvelle Architecture”), is composed of a set of batteries, a dc/dc converter for charging four capacitors, four synchronized spark gap switches, a resonant pulsed transformer that can generate 600 kV in 265 ns pulses, an oil peaking switch and, a dipole antenna
Labourdette, Claude. "Antenne microruban alimentant une source rayonnante en guide d'onde : applications aux antennes large bande et à haute pureté de polarisation dans le domaine des télécommunications spatiales". Toulouse, INPT, 1992. http://www.theses.fr/1992INPT094H.
Pełny tekst źródłaRagad, Hedi. "Etude et conception de nouvelles topologies d’antennes à résonateur diélectrique dans les bandes UHF et SHF". Nantes, 2013. http://archive.bu.univ-nantes.fr/pollux/show.action?id=dbef930c-a344-473d-af02-0038c8fcda98.
Pełny tekst źródłaThis thesis proposes the study and design of new topologies of dielectrics resonators antennas in the UHF and SHF bands. The first part is devoted to the state of the art and to the fundamental characteristics of these antennas. The second part is focused on the design of new types of antennas from the canonical shapes in order to expand their bandwidth for multi-standard applications without changing the distribution of their radiation pattern in free space. Then our interest is focused on the realization of multiband antennas. The first structure is based on the excitation of two modes of a rectangular dielectric resonator antenna, at two different frequencies. The second one is a dielectric resonator antenna (DRAs) with two concentric resonators with different permittivities. They are excited each one on its fundamental mode to obtain a bi-band behavior. In the last part of the study, we are interested in the design of miniature DRAs for UHF RFID applications. We use in this case, materials with high permittivity and we place a layer of metamaterial over the resonator to improve the gain
Linot, Fabrice. "Apport des Surfaces à Haute Impédance à la conception d'antennes réseaux compactes et d'antennes réseaux à très large bande passante". Phd thesis, Télécom ParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00617270.
Pełny tekst źródłaCadilhon, Baptiste. "Etude et réalisation d'un ensemble autonome d'émission d'ondes électromagnétiques de forte puissance". Phd thesis, Université de Pau et des Pays de l'Adour, 2008. http://tel.archives-ouvertes.fr/tel-00424802.
Pełny tekst źródłaRequin, Cédric. "Antennes quasi-auto-complémentaires pour terminaux mobiles multi-standards". Phd thesis, Université Nice Sophia Antipolis, 2013. http://tel.archives-ouvertes.fr/tel-00954410.
Pełny tekst źródłaSow, Mouhamed. "Contribution à la conception de radars géologiques impulsionnels fonctionnant dans un milieu complexe". Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0011/document.
Pełny tekst źródłaThis work presents the design and the realization of an antenna Ultra Wide Band, of low dimensions, for a GPR application working in a complex environment in a frequency band between 70 MHz and 1GHz. This study was registered within the framework of a European project mentioned NeTTUN (New Technologies for Tunnelling and Underground works) who aims at improving the security of the tunnel driving. In this project, the wanted work was to realize a GPR system containing an integrable antenna ULB on a TBM cutter head while working in low frequencies.To realize this antenna by answering the various constraints of dimensions, integration and radiation, a study of antenna insertion in a dielectric material was realized. So analyses were led for time on the subsoil nature encountered, of the compromise between low frequencies and minimal dimensions and especially the integrability of the antenna in a cavity. This study allowed to realize an innovative antenna named Khorn. The Khorn is an association of the K antenna and the Horn antenna. To estimate the performance of the Khorn in its environment, the footprint and the radar range were studied. Measures of validation of the realized prototypes were also made
Le, Minh thuy. "Contribution à la conception d'un système d'identification et de classification de véhicules par les ondes électromagnétiques". Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-00820311.
Pełny tekst źródłaLalj, Hicham. "Conception et caractérisation de filtres et systèmes antennaires reconfigurables chargés par des résonateurs Métamateriaux sub-longueurs d’onde". Thesis, Rennes, INSA, 2014. http://www.theses.fr/2014ISAR0022/document.
Pełny tekst źródłaThe basic structures of metamaterial nourish a promising alternative technology, which aims to meet new demands of miniaturization and performance of reconfigurable radio systems. The work of this thesis based on the combination of miniature and agile cells, according to excitation conditions in the near-field electromagnetic, and a planar microwave devices to achieve a new structure of filters and reconfigurable antenna systems. After a presentation of the state of the art, on both the concept of metamaterial microwave and models of filters and antennas based on metamaterial, our work then propose four orientations. The first relates to the engineering design and simulation of electromagnetic metamaterial unit cells, and the study of miniaturization and agility of the electrical parameters. The second orientation is devoted to the realization of new models of filters based on loading the microstrip line with metamaterial resonators. Two filter models are developed and validated experimentally. The first concerns a band stop filter based on the combination of a microstrip line and SRR resonator. According to the same model, a band-pass filter based on a microstrip line associated with two cells in two different resonant frequencies is proposed. The second model provides a band stop filter based on a microstrip line loaded with CSRR cells, a study miniaturization of this model was presented and used both geometric and electrical optimization of parameters. The agility techniques studied are based on the loading of the cell by active electronic elements such as PIN and varactor diodes which are inserted in appropriate positions. The obtained results showed an interesting variation of the filter parameters. The third focus of the thesis is to introduce new models of association in the near-field, between UWB monopole antenna and metamaterial. The first model relates a monopole antenna associated with SRR cells printed in the substrate close to the excitation line of the antenna. The theoretical and experimental results confirm the behavior stop band around the cell resonance frequency, and a stable performance of radiation in the rest of the reference antenna bandwidth. For the second model the monopole is loaded by the SRRs CSRRs cells. After optimization of the cells excitation conditions, the simulation results confirm both the stop band behavior around the cell resonance frequency and the stability of the radiation pattern. The latest orientation concerns the realization of two new antenna systems with multi frequency constraints for cognitive radio application. The first system is based on a monopole antenna and tunable SRRs cells. The measurement and simulation results show a UWB behavior with two reconfigurable and controllable filtered bands. The second new systems tempt to reply the antennas systems requirements used in the cognitive radio. All results showed a flexibility of switching from antenna-sensor (ULB) to a communication antenna with tunable and controllable narrow band
Duplouy, Johan. "Wideband Reconfigurable Vector Antenna for 3-D Direction Finding Application". Thesis, Toulouse, INPT, 2019. http://oatao.univ-toulouse.fr/24404/1/Duplouy_Johan.pdf.
Pełny tekst źródłaLe, Minh Thuy. "Contribution à la conception d'un système d'identification et de classification de véhicules par les ondes électromagnétiques". Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENT003/document.
Pełny tekst źródłaThe activities of passenger and goods transport are constantly increasing worldwide and especially in the European Union, including the edge of tolls. To improve the fluidity and reduce the risk of congestion, one of the solutions is automatic toll payments. The objective of this thesis is to enhance the performance of vehicle identification systems and to contribute to develop a design of a classification vehicles system by using electromagnetic waves for free-flow electronic toll collection system application. This system allows an automatic payment without stopping vehicles. The first part of this thesis deals with the study of two vehicle identification systems: UHF RFID and DSRC. Five new antennas were realized with the purpose to increase the communication range as well as to reduce the size and cost of the system. They are high gain and easy to be industrialized. The second part of this thesis is devoted to the study of a classification of different types of vehicles from the scattered waves captured by the system. Three methods of vehicle classification are proposed and tested in the road environment. Such system detects the presence of vehicle and measures the distance between vehicle and itself with a good accuracy. The principle of the system is based on Ultra-Wideband radar technology in which transmitting signal with a very short duration pulse is used
Hebib, Sami. "Nouvelle topologie d'antennes multi-bandes pour applications spatiales". Phd thesis, Université Paul Sabatier - Toulouse III, 2008. http://tel.archives-ouvertes.fr/tel-00347683.
Pełny tekst źródłaAlzein, Hala. "Développements de nouvelles architectures d’antennes reconfigurables pour les applications de télécommunications de 5ème génération". Thesis, Limoges, 2020. http://www.theses.fr/2020LIMO0014.
Pełny tekst źródłaThe fast development of wireless communication led to an increasing demand for new developments on antennas. These developments were backed by an urgent need for more complex architectures due to the need of reconfigurability in terms of frequency, reliability, radiation pattern and power consumption. In order to cover those needs, this work is based on an original reconfigurable antenna with a simplified feed network developed by XLIM laboratory, to offer an attractive tradeoff in terms of performances, complexity and cost. This new architecture is based on previous works from the laboratory (2012-2015) and a first proof of concept working at 2.45 GHz. The work proposed for this PhD is based on the development of this new architecture to manage the problems of periodic antenna arrays. Two main axes were developed during this work. The first axis consists to demonstrate the interest of this concept to manage the active VSWR of each excited element using loads connected to the parasitic elements, avoiding the need for circulators, while reducing the complexity of feed network. The second part of our work is dedicated to illustrating the potentialities of these antennas to reduce the grating lobes, while defining a constraint on the level of sidelobes. A manufactured prototype is presented in order to experimentally validate the potentialities of these antennas
SONNERAT, Florence. "Développement d'antennes innovantes pour les terminaux mobiles 4G tenant compte de l'interaction avec l'utilisateur : solutions circuits et antennes envisageables". Phd thesis, 2013. http://tel.archives-ouvertes.fr/tel-00908829.
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