Tesis sobre el tema "Antenne à dépointage électronique"
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Clemente, Antonio. "Conception d'antennes à réseaux transmetteurs à dépointage et formation de faisceau". Rennes 1, 2012. http://www.theses.fr/2012REN1S094.
Texto completoThis PhD thesis investigates the design and realisation of electronically reconfigurable transmit-array antennas. A transmit-array is composed of one or more focal sources illuminating a first antenna array operating in receive mode and connected, using phase-shift elements, to a second antenna array operating in transmission mode. The incident power received on the first array, as in the case of a lens, is transmitted in the free space and can be focused or collimated by tuning the transmission phase of the unit-cells in order to obtain a specific phase distribution across the array aperture. Beam-steering and beam-forming can be achieved using electronically tunable unit-cells. A theoretical study of transmit-arrays performances has been carried out using an in-house CAD tool based on analytical formulas. The reduction of the focal distance using multiple feeds and the reduction of the spill-over losses using a beam-formed focal source have been investigated as well. A linearly-polarized electronically reconfigurable transmit-array at X-band frequencies has been designed and demonstrated. This prototype is composed of 20×20 unit-cells. 800 PIN diodes have been integrated on the array in order to control the transmission phase of each unit-cell. A maximum broadside gain of 22,7 dBi, a bandwidth of 1,56 GHz (15,6% at 10 GHz), a total efficiency of 52,9% , and a 2D beam-steering capability of ±70% have been measured. Finally, the use of RF-MEMS switches to reduce the unit-cell insertion losses and the transmit-array total power consumption has been investigated
Diaby, Fatimata. "Réseaux transmetteurs reconfigurables pour le dépointage et la formation de faisceau en bande millimétrique". Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT125/document.
Texto completoNowadays, transmitarray antennas are of great interest for many civil and military applications in frequency bands between 10 and 110 GHz (5G mobile networks, point-to-point communication systems, radars, etc.).This thesis aims to make major innovations in modeling and design of transmitarray antennas for Ka-band applications (28-40 GHz). It focuses on the development of numerical tools, and the design and demonstration of several prototypes with advanced functionalities, such as passive (broadband or multibeam) and active (at electronic reconfiguration) transmitarrays.The first part of the work consists of a theoretical analysis of the transmitarray antenna. In a first step, the impact of the phase compensation method on the performance of the transmitarray is studied. The phase compensation law of the quasi-spherical wave incident on the array aperture is calculated using two methods called constant phase compensation and true-time delay (TTD) compensation. The numerical results show that TTD compensation allows an increase of the transmitarrays bandwidth and a reduction of the beam squint as compared to constant phase-shift compensation. In a second step, the operating principle of facetted transmitarrays is described in detail. The numerical simulation of a 3-facet transmitarray is validated through 3-D electromagnetic simulations. For a certain facet angle, the bandwidth and the beam scanning capability of the TA are improved at the expense of the gain.The next step of the work concerns the design and prototyping of two passive transmitarray antennas, one with a collimated and a large bandwidth, and the other with four fixed beams. The two transmitarrays are based on a 3-bit unit-cell providing two functions, namely the phase compensation and the polarization conversion from linear to circular. The passive beam-collimated transmitarray exhibits a measured gain of 33.8 dBi (corresponding to an aperture efficiency of 51.2%) and a 3-dB gain-bandwidth larger than 15.9%. The quad-beam transmitarray phase distribution has been optimized by a genetic algorithm code coupled with an analytical tool. The array is designed to radiate four beams at ±25° in the horizontal and vertical planes at the optimization frequency.The last part of the work aims to the design of a 27-31 GHz reconfigurable transmitarray antenna. Initially, an active unit-cell with four phase states (2 bits) in linear polarization was designed and validated experimentally. It consists of six metal layers printed on three substrates. The radiating elements are rectangular patch antennas, each of them including two PIN diodes to control the transmission phase. The operating principle of the unit-cell has been experimentally validated with a minimum insertion loss of 1.6-2.1 dB and a 3-dB transmission bandwidth of 10-12.1% for the four phase states. 0°, 90°, 180° and 270°.Then, this unit-cell was used for the design of a reconfigurable transmitarray antenna comprising 14 × 14 unit cells and 784 PIN diodes. A prototype was realized and characterized, it presents a measured maximum gain of 19.8 dBi, corresponding to an aperture efficiency of 23.5%, and a 3-dB bandwidth of 4.7 GHz (26.2% at 30.9 GHz). Despite some faulty elements, this prototype validates the operating principle and the feasibility of Ka-band transmitarray antennas with a 2-bit phase quantization. It is one of the first demonstration of such an antenna in the current state of the art
Duran, Venegas Juan Antonio. "Reconfigurable Metasurfaces for Beam Scanning Planar Antennas". Thesis, Toulouse, INPT, 2016. http://www.theses.fr/2016INPT0102.
Texto completoWe are studying the implementation of 'Scanning Antenna dedicated to the applications of satellite communications geostationary. The structures developed are suitable for to be on board an airplane or a train. The architecture of the antenna developed consists of a double linear network in two transverse dimmensions. The scan in each network is provided by the lines coplanar to metamaterials controlled by varactor. We porposons of new methods characterization of discontinuities coplanar online for the line design. In addition, a energy harvesting system has be designed to feed radiating elements and tested with patch different antennas. Finally, we are considering co-integration radiating structures and CRLH lines as well as control electronic by the diodes
Fechine, Sette Elmo Luiz. "Circuits intégrés millimétriques en bande Ka pour une antenne à pointage électronique pour les télécommunications avec des satellites géostationnaires ou des constellations de satellites". Electronic Thesis or Diss., Limoges, 2024. http://www.theses.fr/2024LIMO0002.
Texto completoThis work presents the design of active integrated circuits intended for integration into an electronically steered antenna for Ka-band satellite communications. Firstly, the manuscript introduces the context of the study, discussing the main concepts and characteristics of this type of antenna. Subsequently, two key blocks of the transmission chain are studied in detail and designed: a variable gain power amplifier and three controllable phase shifters. The circuits are implemented using two SiGe BiCMOS technologies: BiCMOS9MW and SG13G2. Finally, the post-layout simulation results are presented and compared to the project specifications as well as the state of the art
Breahna, Tudor Iulian. "Conception d'une antenne à bande élargie en technologie microruban, pour une antenne-réseau à balayage électronique". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ38037.pdf.
Texto completoYuan, Tangjie. "Antenne à métamatériaux pour les applications aéronautiques". Paris 10, 2012. http://www.theses.fr/2012PA100215.
Texto completoThis thesis concerns sub-project SP1 from “Matériaux et Structures Intelligentes pour l’Électromagnétisme” (MSIE) is a need for manufacturers will be constituting a genuine integration of antenna structures in aircraft structure as integrated equipment. This approach became possible through the use of new materials called "metamaterials" structures that could be used to form future integrated antenna structures on aircraft. We will evaluate the concepts of antenna structures embedded in the fuselage and/or drift plane. The thickness of the equipment should be less than 20 mm (excluding connector dimensions of 130 MHz -140 MHz). We will study two types of solutions: solution 1 and solution 2 respectively to the VHF frequencies. The first is a new compact antenna using a circular slot and shorted shorting-pins loading techniques behaves as a standard monopole antenna. The second antenna is the bent monopole antenna based a dual-layer EBG structure ground plane. The simulations and the optimizations of the two antennas were made in the VHF band. However, experimental facilities in the VHF are not available in our laboratory. The two antennas were again studied with a scale factor of 1/10 or 1/15 to operate around 1. 3 GHz or 2 GHz respectively. The performance of the two antennas (TOS, gain, radiation pattern) will be measured experimentally and compared with the theoretical results obtained by simulation. According to experimental results, one of the two configurations will be selected for the manufacture of an antenna at scale 1. This is the solution 2. This thesis is presented in three chapters: The first chapter presents the properties of a standard monopole antenna, and we will present a brief overview of the state of the art antennas. The second chapter, we present the design, optimization, and numerical and experimental characterizations of the circular slot antenna using the loading techniques: Solution 1. The simulated and measured results are in excellent agreement. An experimental bandwidth of 5. 1% (S11 = -10 dB) is presented with a maximum gain of 3. 7 dB at a frequency of 2. 04 GHz (in the azimuthal plane). In addition, several antenna parameters are analyzed to improve the antenna. Particularly, the bandwidth of the antenna has been extended to a wideband up to 11. 5% with an important role in radius of shorting pins. In the third chapter, we present the design, optimization, numerical and experimental characterizations of the metamaterials bent monopole antenna operating at 1. 3 GHz: Solution 2. A prototype of the antenna based on dual-layer EBG structure with a very low height (λo/36) was proposed and fabricated. The antenna was measured with a wide bandwidth of 24. 4% (S11 = -10 dB). The measured radiation pattern is represented with a maximum gain of 8. 7 dB. Results between simulations and measurements have a very slight difference. An array of the two identical metamaterials antennas disposed on both sides of the aircraft plane is to forms a Sabre-type antenna. The experimental radiation patterns are combined and analyzed. The antenna has a bandwidth ~ 24. 4% and a maximum gain of 8 dB at 1. 45 GHz. Finally, parametric studies based on all the validated experimentally simulating results are possible to improve in particular the bandwidth without major changes
Panaia, Patrice. "Reconfiguration dynamique d'une antenne pour partage de fonctions". Nice, 2006. http://www.theses.fr/2006NICE4084.
Texto completoIn this work, we present the frequency agile antennas study, and the design of such reconfigurable antennas based on RF MEMS. A state of the art on agile antennas an RF MEMS allowed to RF MEMS to choose the suitable devices. A first topic concerns a PIFA antenna with an open slot on the radiating element. The addition of a short circuit in a given position allows to obtain the resonance frequency shift. The short circuit made up, in a first time, with a piece of copper placed inside the slot, allows to model the MEMS active component? The final goal being to replace this short circuit by a RF MEMS placed on the radiating element, measurements were made to validate the concept. On this antenna, the MEMS position is optimized and the DC bias circuitry interactions are minimized, by using microstrip lines on the radiating element. Two prototypes of antennas with RF MEMS allowed to obtain the resonance switching. A second printed antenna fed by coplanar waveguide line was studied. This IFA antenna has to allow a switching between the bandwidth of the IEE802. 11b/g and IEE802. 11a/h standards. The switching is realized by two MEMS activated simultaneously. The first simulations were made by modelling the RF MEMS by two air gaps for the “OFF” state and by the whole structure for the “ON” state. A analyze on the location of the bias activation of the MEMS was made to optimize the concept. The passive structure gives results close to the simulation, but some frequency shifts can be observed on the active structure. Two types of packaged RF MEMS series switches were used. The first one is thermally actuated with a 2V bias. The second one, which os electrostatically actuated, needs 20 supply voltages. Therefore a new reconfigurable IFA antenna between ISM 24 and 61 GHz bands was simulated on a high resistivity silicon substrate to allow the integration of RF MEMS and the antenna
Damaj, Lana. "Antenne versatile intriquée". Electronic Thesis or Diss., Paris, ENST, 2013. http://www.theses.fr/2013ENST0010.
Texto completoThis thesis aims to develop wideband antennas interrelated with a filter, which we have defined as versatile intricate antennas. The antenna is versatile as it provides wide bandwidth (more than one octave) and has the capability to generate two orthogonal polarizations. On the other hand, the filter for harmonic rejection and the matching network are integrated parts of the radiating element and give it the intricate character.The first study is concentrated on designing a dual polarized antenna with a wide stop filter integrated to the feeding network. This filter enables to reject harmonics and unwanted response. The complete structure is compact with a size of 0.9 λ0x0.9 λ0, λ0 being the free space wavelength at the lowest frequency. In order to improve the compactness of the whole system and to cover more standards, we present a single and dual polarized wideband Harmonic Suppressed Antenna (HSA). This work explores the different techniques used to design a HAS. The proposed antenna is simple in structure but versatile in applications. In this approach, radiating element, filter for harmonic rejection and matching network, which are traditionally separated circuits, are incorporated into a single compact unit. The total size of the antenna is 0.53 λ0x0.53λ0. The final chapter aims to study the previous intricate antenna with a new wideband Artificial Magnetic Conductor (AMC) structure as reflector in order to obtain a low profile and directive antenna
Verhulst, Anne. "Intégration d'une antenne acoustique à haute résolution sur une plateforme multi capteur". Paris 11, 1995. http://www.theses.fr/1995PA112209.
Texto completoMensi, Mohamed. "Hyperthermie microonde : modélisation et contrôle d'une antenne multisource". Toulouse, INPT, 1986. http://www.theses.fr/1986INPT033H.
Texto completoLeforestier, Florian. "Concept Avancé de Radar à Antenne et Impulsion Semi-Synthétique (CARAISS)". Paris 10, 2002. http://www.theses.fr/2002PA100094.
Texto completoUWB (Ultra "aide Band) is becoming an essential technique in a large variety of domains like ECCM (Electronic Counter Counter Measure), GPR (Ground Penetrating Radar) and radar imaging (SAR -Synthetic Aperture Radar-, ISAR -Inverse Synthetic Aperture Radar-;. . . ). Technology used te generate UWB is at present based on classic pulse radar techniques, which are band and power-limited, due to hardware limitations. The two major consequences are unachievable bandwith requirement and high coûts associated with high-teck hardware. CARAISS is a project aimed not only at overcoming this lirait but also at doing it at low cost with classical technology. The studied concept was te cluster narrowband channels transmitting simultaneously in order to provide a theoretically unlimited bandwith and a real pulse as close as needed to a Dirac peak
Damaj, Lana. "Antenne versatile intriquée". Thesis, Paris, ENST, 2013. http://www.theses.fr/2013ENST0010/document.
Texto completoThis thesis aims to develop wideband antennas interrelated with a filter, which we have defined as versatile intricate antennas. The antenna is versatile as it provides wide bandwidth (more than one octave) and has the capability to generate two orthogonal polarizations. On the other hand, the filter for harmonic rejection and the matching network are integrated parts of the radiating element and give it the intricate character.The first study is concentrated on designing a dual polarized antenna with a wide stop filter integrated to the feeding network. This filter enables to reject harmonics and unwanted response. The complete structure is compact with a size of 0.9 λ0x0.9 λ0, λ0 being the free space wavelength at the lowest frequency. In order to improve the compactness of the whole system and to cover more standards, we present a single and dual polarized wideband Harmonic Suppressed Antenna (HSA). This work explores the different techniques used to design a HAS. The proposed antenna is simple in structure but versatile in applications. In this approach, radiating element, filter for harmonic rejection and matching network, which are traditionally separated circuits, are incorporated into a single compact unit. The total size of the antenna is 0.53 λ0x0.53λ0. The final chapter aims to study the previous intricate antenna with a new wideband Artificial Magnetic Conductor (AMC) structure as reflector in order to obtain a low profile and directive antenna
Blanchard, Louis. "Conception d´antenne avec optimisation des lobes réseau : application au partitionnement en sous réseaux d´une antenne radar". Paris, ENMP, 2007. http://www.theses.fr/2007ENMP1474.
Texto completoThe synthesis of an array antenna is a inverse problem. The applications of this problem are civil : telecommunication and satellites, but also military : air defense radars. In an array antenna, each element is weighted using the ponderation term and consequently the array antenna beamforming can evolves toward a desired pattern without any mechanical movement of the antenna. The aim of this study is the analysis of a new concept in the antenna synthesis problem, based on a bi-criteria formulation of the antenna beamforming, which is an alternative to the problem of pattern synthesis. Moreover, in order to solve antenna synthesis problem based on this bi-criteria formulation, we need to address two major areas of mathematical analysis. The first area concerns differentiable optimization problems under constraints, consisting in optimizing both ponderation and geometry of the array antenna, and for which a deterministic method based on a tangential Newton-Raphson algorithm is used. The second area concerns the topological optimization problem by moving domains used in the problem of optimal partitioning of an array antenna into sub-array, in the case of radar made by a thousand elements. To conclude, the bi-criteria optimization method can be used, both as in a civil context for array antennas dedicated to mobiles phone, and as in a military context for air defense radars
Rmili, Hatem. "Etude, réalisation et caractérisation d'une antenne plaquée en polyaniline fonctionnant à 10 GHz". Bordeaux 1, 2004. http://www.theses.fr/2004BOR12888.
Texto completoYann, Clément. "Modélisation électromagnétique de cellules actives environnées : application à l'analyse et la synthèse d'une antenne reflectarray à balayage électronique". Rennes, INSA, 2012. https://tel.archives-ouvertes.fr/tel-00781799.
Texto completoReflectarray antenna is a promising solution for space communications and radar applications as it combines attractive features of reflector and array antennas. A reflectarray consists of an array of reflecting cells fed by a horn antenna. Each cell introduces an appropriate phase-shift to the incident wave to steer the main beam in a desired direction. Thanks to the primary feed horn, the complex feed network that characterizes phased array antennas is not required anymore. This thesis focuses on the electromagnetic simulation of reconfigurable reflectarrays (RRA) with electronic beam scanning. The current simulation approaches of RRA ignore or approximate the mutual coupling effects between cells which lead to prediction errors on the radiation pattern. The simulation of RRA generates complex treatments and requires significant computation time and memory resources. The simulation challenge is to reduce the computation time while preserving high accuracy so as to optimize the radiation performances and the design process. In this context, two innovative methods have been proposed: - The first method is dedicated to the thorough analysis of the field radiated by the reflectarray. It combines the 'surrounded-element' approach developed by M. -A. Milon and the compression technique which is generally used for circuit analysis. The extension of the compression technique to compute the field radiated by active cells in their actual environment is the key contribution of the method. The second method computes the phase responses of an active cell taking into account mutual coupling from the surrounded cells. The responses are used to select the optimal configuration of the states of the cells so as to provide a pencil beam in a specific direction. Different test cases of active arrays with PIN diodes are considered to demonstrate the performance and the applicability of the two methods for solving the electromagnetic problems associated with RRA. The validation procedure has proved that the methods offer an interesting alternative to classical approaches. The methods are applied to an X-band RRA designed by Thales Systèmes Aéroportés and the space agency CNES. This study has shown that the two methods meet the scientific and industrial objectives in terms of prediction accuracy and short computation time
Linardou, Irini. "Antenne Vivaldi : potentialités d'applications en ondes millimétriques". Nice, 2000. http://www.theses.fr/2000NICE5455.
Texto completoTahani, Abdelkrim. "Conception d'une antenne réceptrice omnidirectionnelle et multipolarisations dédiée aux récepteurs portables de radiomessagerie". Metz, 1995. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1995/Tahani.Abdelkrim.SMZ9521.pdf.
Texto completoThe receivers of radio-broadcasting in general and espacially those of paging receiver are equipped with essential element which is called the antenna. This element is defended as device of coupling between radiated wave in free space and the transmission line which leads to the receiver. In principle, such compact portable receivers use whether inductive antenna particulary sensitive at magnetic field, or capacitive antenna sensitive at electric field. The technological progress of such receivers results for the most part from conception and development of compact antenna less cumbersome characterised by a sensitivity less or equal to 35 dBuV/m. The essential objective of this work is to show the technical and industrial feasibility of a new type hybrid omnidirectionnel and multipolarisation antenna intends to paging receivers operational in frequency band II (87. 5 - 108 MHz). Two ideas are essential to achieve a such antenna : the first one consists in associating two antennas which were developed at TDF-C2R. It concerns one antenna with miniaturised magnetic core and loop in short circuit. The formed so a resultant antenna composed of two inductive antennas perpendicular. Both of then sensitive at magnetic field. The second consists of electronic system indispensable is the extraction of the signal caring the information. So, the system suggested presents a particular advantage which is based on its simplicity them on its cost and its reliability. The role of a such system is to ensure the total of a such system is to ensure the total of both signals shifted of 90°
Ouedraogo, Samir. "Antenne Multifonction pour Radar et Communication". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLC010/document.
Texto completoIn order to respond to the increasingly demand of new services, the objects we use on a daily basis (such as mobile phones, cars, airplanes etc.), tend to integrate more and more radio systems while the space available is limited. These radio systems require the use of many antennas that must meet multiple requirements such as compactness, isolation, costs, etc. A smart-phone, for example, contains several antennas for global navigation satellite system (GNSS), WiFi, TV, FM radio, Bluetooth, near-field communications (NFC) and the number is expected to increase as new systems are added. Another example is in airborne platforms where multiple functions such as communication, navigation, radar, electronic warfare are used. This leads to the need of reducing the number of associated antennas by regrouping several radio functions into a single antenna. However, combining the functionality of several antennas into one shared radiating element while maintaining the functionality of the various radio systems presents a great challenge. During its Ph.D, J. Euzière demonstrated the possibility to combine a radar function and a secondary function from a 16-monopole array originally dedicated to radar operation by using Time Modulated Array (TMA) technique. By this way, the two functions were operating at the same frequency and the system was powered by a single source.The main objective of this thesis is to propose a more compact antenna (a single antenna) dedicated to radar and communication operations instead of using antenna array as J. Euzière did it. The idea is to start from an existing antenna solution and make the necessary modifications to add a second function without adding additional surface and complexity. As we are interested in radar applications, we will choose a directive antenna: a horn antenna. The goal is then to study the possibility to modify the radiation pattern of the horn antenna through controllable elements (slots) and to transmit a direct modulated signal at the antenna level for the communication function. Furthermore, polarization diversity is an attractive way to increase the isolation between two applications. Thus, this aspect will be taken into account in the design of the antenna solution
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.
Texto completoThis 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
Vahdani, Mohammad. "Conception d'antennes compactes ultra large bande bipolarisation". Phd thesis, Télécom ParisTech, 2008. http://pastel.archives-ouvertes.fr/pastel-00006086.
Texto completoHoltrup, Gerrit. "Conception d'une antenne plate à large bande à balayage électronique commandée par incréments de temps". Rennes, INSA, 2002. http://www.theses.fr/2002ISAR0002.
Texto completoQasimi, Ahmed. "Contribution à la mise en oeuvre d'une micro-sonde de Hall associée à une antenne ferromagnétique : bruit et résolution spatiale". Caen, 2004. http://www.theses.fr/2004CAEN2022.
Texto completoHarrabi, 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.
Texto completoDespite 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
Huitema, 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.
Texto completoGiven 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
Lohou, Anaël. "Conception de circuits intégrés pour antenne à pointage électronique destinée aux télécommunications par satellite en bande Ka". Thesis, Limoges, 2018. http://www.theses.fr/2018LIMO0096/document.
Texto completoIn a world where the information is moving faster and faster, it is important to be able to stay connected continuously. Some new solutions for air transport connectivity are in development thanks to the rise of satellite communications. This thesis work is part of an electronically steerable antenna array project, developed as a solution to achieve In-Flight Connectivity in Ka-band. A state- of-the art review on electronically steerable antenna arrays is also presented. In these arrays, each radiating element needs a specific amplitude and phase to obtain a scanning beam by adding their contribution. This thesis focus on the design of a GaAs MMIC chip inclusion two functions: a phase shifter and a variable-gain low-noise amplifier. The simulation and measurement results are presented for these two functions
Caudrillier, Pierre. "Contribution à la modélisation des couplages antenne/structure par technique multidomaine". Toulouse 3, 2003. http://www.theses.fr/2003TOU30148.
Texto completoVerriest, Eric. "Conception et mise en oeuvre en temps réel d'un système de soustraction de bruit adaptatif pour antenne sonar". Lille 1, 1998. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/1998/50376-1998-181.pdf.
Texto completoBaron, Samuel. "Polymère souple pour antenne patch électriquement accordable en bande X : conception et caractérisations". Nantes, 2015. https://archive.bu.univ-nantes.fr/pollux/show/show?id=cd5ee96a-50ba-475f-b933-7edc17cf7cc3.
Texto completoIn communication systems, smart antennas with large frequency tunability (agility) have been gaining worldwide attention over the past few years due to the proliferation of global wireless communication standards in close proximity to one another. However, conventional solutions use electronic components which induce additional costs and make the system more complicated. Moreover, the electronic devices have moved from rigid to flexible dielectric substrates to reduce the cost and to obtain stretchability and conformability properties. The goal of this thesis is to put together these two topics. The chosen original approach consists of the mechanical reconfiguration of antenna patch printed on a soft membrane substrate with electrostatic actuation in X band, at around 10 GHz. Moreover, a new polymeric substrate was employed in this structure, the polyurethane (PU). Firstly, the technological processes required to realize the antenna patch on the PU substrate were developed. Then, the dielectric properties of polyurethane films were measured on a large frequency band in order to define the antenna patch dimensions using high frequency simulations. Finally, the first antennas patch realized and characterized have a figure of merit Frequency tunability/Voltage higher than the state of the art. Preliminary studies were also carried out to explore various feasible ways for improved the antenna systems performances
Thévenard, Julian. "Contribution à la conception à bas coût d'antennes 3D reconfigurables : solutions originales d'intégration en technologie plastique pour les systèmes sans fil du futur". Brest, 2008. http://www.theses.fr/2008BRES2011.
Texto completoThis thesis is dedicated to the design of 3D smart antennas for forthcoming wireless devices. Our research work has been motivated by the actual wireless trends leading to service concentration within WLAN and device miniaturisation. Thus, antenna design is nowadays guided by size constraints and their capacity to deal with fading interference, wireless environments while improving the performances of devices in terms of communication quality, power consumption. This thesis presents a multi-sector antenna solution associating many Vivaldi-antennas to provide a solution for the targeted application which is an embedded system constituting of high definition wireless cameras. A theoretical analysis of the Vivaldi antenna is first performed and then a novel concept of multi-sector antenna has been introduced and validated. Then, in order to target consumer market and to reduce the manufacturing costs in high volume production, the metallized molded plastic technology which enables molding 3D complex structures has been retained. An original without-welding transfer system has been developed for integrating the antenna to the rest of the system. The characterization of a prototype has resulted in the validation of the use of plastics for such applications. This antenna has been integrated in a wireless camera ; a protective radome having as additional property to improve the overall performances of the device is finally designed. This simplified integration procedure associated to a monitoring of the performances and the flexibility of the system makes it a good candidate for various applications like domestic WLAN, mesh networks or for MIMO technology
Yann, Clement. "Modélisation électromagnétique de cellules actives environnées - Application à l'analyse et la synthèse d'une antenne reflectarray à balayage électronique". Phd thesis, INSA de Rennes, 2012. http://tel.archives-ouvertes.fr/tel-00781799.
Texto completoPorgès, Tristan. "Détection et classification de cibles en imagerie SAR haute résolution". Nice, 2012. http://www.theses.fr/2012NICE4000.
Texto completoThis thesis is concerned with a complete processing chain for terget detection and recognition in high resolution SAR images. It consists in two steps : the automatic target detection (ATD) and the automatic target recognition (ATR). Algorithms using a sliding window over images generally don’t provide good results for multitarget detection. The probability distribution mixture model proposed for pixel intensity distribution provides good detection rates in such configurations. This approach characterises each image by means of two distributions : one related to the targets and one related to the background clutter. The algorithm used to estimate the mixture parameters allows to calibrate the detection threshold to get a desired false alarm rate. A supervised classification algorithm based on a tensor analysis is used for the recognition step. A SAR database is composed of a set of images of targets with different parameters : aspect angles, graying angles… These images form a high-order tensor whose each dimension is associated with a parameter. HOSVD (high order singular value decomposition) is applied to this tensor and a decision criterion based on this decomposition labels the unknown target or reject it if it doesn’t belong to the training database. The MPCA (multilinear principal component analysis) algorithm proposed in this thesis provides hign recognition rate and is able to estimate all the parameters of one tested image. Moreover, it allows a very high compression rate of the training database. Simulation results illustrate the performance of both proposed detection and recognition algorithms, including comparisons with other existing methods
Kallel, Asma. "Modélisation et conception d'une antenne plasma à balayage basée sur des ondes de fuite". Phd thesis, Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2514/.
Texto completoIn this work, a beam scanning leaky-wave antenna working at a fixed operating frequency and constructed from a grounded plasma layer is proposed. The radiation angle can be tuned by the plasma electron density which is controlled by the power. A 2D theoretical model based on a canonical structure is proposed to study the leaky waves. The antenna parameters (plasma thickness, length and permittivity) are dimensioned using this theoretical model, at 10 GHz, and a microwave source is chosen to excite the antenna. The scanning range of about 60° needs a plasma reaching an electron density of. In a second step an inductively coupled plasma source is chosen since it meets the dimensioning requirements. The measurements of the plasma parameters confirm the requirements. Finally, the antenna prototype is designed
Kallel, Asma. "Modélisation et conception d'une antenne plasma à balayage basée sur des ondes de fuite". Phd thesis, Toulouse 3, 2014. http://oatao.univ-toulouse.fr/14142/1/kallel.pdf.
Texto completoDia, Yaakoub. "Optimisation par conception conjointe de dispositifs multifonctions filtre-antenne compacts et agiles". Thesis, Limoges, 2016. http://www.theses.fr/2016LIMO0051/document.
Texto completoThe aim of this thesis is to design a new tunable and compact multifunctional device (filters, antennas) based on the co-design of an antenna and the associated filter. The subsystem needs to fit with electrical specifications for ISM band applications at 2.45GHz while being integrated and compact. The antenna and the filter are jointly developed on particular impedances where the antenna has a high radiation efficiency. The filter is optimized to adapt the antenna on its optimal impedance and introduce minimal losses. The work has initially been focused on the co-design and the co-integration of functions to finish on the tunability of the filter/antenna subsystem design
Amaidia, Glay. "Caractérisation des sources acoustiques en champ proche et lointain par l'intermédiaire d'une antenne linéaire multicapteur". Compiègne, 1994. http://www.theses.fr/1994COMPD739.
Texto completoLemorton, Joël. "Étude des possibilités d'intégration d'un déphaseur à ferrite en structure microruban dans une antenne à réseaux et à diagramme adaptatif". Toulouse, ENSAE, 1986. http://www.theses.fr/1986ESAE0010.
Texto completoMage, Lucile. "Caractérisation d'un réacteur plasma de type résonance cyclotronique électronique à antenne longue : évaluation du réacteur pour un processus de dépôt". Toulouse 3, 1997. http://www.theses.fr/1997TOU30174.
Texto completoLu, Yingxian. "Récolteuses d’énergie cinétique électrostatique (e-REC) à basse fréquence pour applications de communication RFID et électronique portable". Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1077/document.
Texto completoA growing number of portable and wearable electronics results in an increasing demand of sustainable and localized power supply module of small size and weight, and offering high output power. As a promising choice for the power supply, Kinetic energy harvesters (KEHs), transforming the ambient vibrations or motions into electrical energy, are studied intensively in recent yeas. The performance of the miniature KEHs available in literature are generaly confined by their sized. The ambient vibrations are usually abundant in low frequency, which is also a major factor restricting the output power of the KEH. In order to enhance the power output, we should improve the energy conversion efficiency, which is related to the transduction principle. This work presents the improvement of the output power of low frequency electrostatic KEHs through impact-coupled mechanical frequency up conversion mechanism, and proposes a predictive numerical model of the prototype which considers the squeeze film air damping effect and the impacts in the prototype. A prototype is proposed with improved geometry of capacitive module reducing the air damping force. Alternative approaches to adjust the KEHs to varied applications are proposed, including a fully flexible KEH designed for wearable electronics, and a 2-D low frequency KEH that is sensible to vibrations along two orthogonal directions. In addition, a fully energy-autonomous RFID tag system implementing the low frequency KEH as the power supply module and a semi-passive RFID communication module is presented
Chahat, Nacer. "Antenne, propagation et interaction avec le corps pour les applications de type réseaux corporels sans fil en micro-ondes et en millimétrique". Rennes 1, 2012. http://www.theses.fr/2012REN1S079.
Texto completoRecent progress in miniaturization of communicating devices and design of smart networks has triggered increased interest to body area networks (BAN) having a very strong potential for near future applications including military, personal healthcare, sport, space, entertainment, smart home, etc. This increasing attention to BAN and PAN (Personal Area Networks) applications has led to the development of textile sensors that can be easily integrated into clothes and to the buildup of high-data-rate wireless devices. The PhD thesis project has two main objectives. First, several microwave textile antennas have been optimized and fabricated to evaluate the interaction with the human body. The impact of the human body on the antenna performance is of great importance since it can directly impact the efficiency of on-body devices and global performances of the system. The power absorption in the body was also studied using realistic body models with different morphologies. Second, the unlicensed 57-64 GHz band have been studied in the wireless BAN context since it provides several advantages compared to microwave BAN. In particular, very high data rates can be reached (up to 5 Gb/s) whilst providing high level of security and low interference with adjacent networks. Besides, the on-body devices are much smaller at millimeter waves compared to those operating at microwaves
Hajj, Mohamad. "Conception, réalisation et caractérisation de nouveaux types d'antennes sectorielles à base de matériaux BIE métalliques pour télécommunications terrestres". Limoges, 2009. https://aurore.unilim.fr/theses/nxfile/default/f49a2783-fa7c-4333-8dbf-8c14921cbd6e/blobholder:0/2009LIMO4032.pdf.
Texto completoThis thesis investigates several developments related to terrestrial wireless communication networks. The presented work is focused on studying base station antennas using metallic electromagnetic band gap (M-EBG) materials. These structures offer a sectoral radiation pattern in the azimuth plane with a high gain. Four aspects were addressed during this manuscript : 1. The first allows us to understand and highlight attractive properties of M-EBG materials, then exploit these properties for the design and implementation of sectoral M-EBG base station antennas. 2. The second is to enhance and increase M-EBG sectoral antenna performances in terms of gain and bandwidth. For that, we have presented a new technique for increasing the Gain Bandwidth Product. 3. The third is to achieve many versatile capabilities of the antenna. This versatility has been improved thanks to multipolarized, multi-frequency behavior of the M-EBG sectoral antenna. 4. The fourth is carried out a feasibility study of a novel beam scanning antenna array obtained by assembling identical M-EBG sectoral antennas, then the same structure is used to design an agile antenna suitable for many applications inculding telecommunication and RADAR
Chreim, Hassan. "Etude d’antennes BIE multifaisceaux agiles : Amélioration de la couverture omnidirectionnelle en azimut". Limoges, 2009. https://aurore.unilim.fr/theses/nxfile/default/d6b37cc2-4d85-4d7b-9f13-aadb529b6d24/blobholder:0/2009LIMO4005.pdf.
Texto completoThis manuscript is dedicated to the study of new concept of EBG multibeam active antennas; in order to ameliorate the omnidirectional coverage achieved by other types of antennas. First, a design method of coaxial EBG multibeam antenna, based on the omnidirectional coaxial EBG antenna has been submitted. Then, the design of a 4x90° coaxial EBG multibeam active antenna has been presented. The strong coupling between the sources in the horizontal plane appears when their number increases. That is why we began to study a new type of EBG multibeam antenna: the EBG multisectoral antenna. This structure has been studied for several types of applications requiring active antennas. A prototype fabrication of the EBG multisectoral antenna validated our concept. An SP6T based switching system for the prototype is also presented
Coulon, Martial. "Contribution à la détection de modèles paramétriques en présence de bruit additif et multiplicatif". Toulouse, INPT, 1999. http://www.theses.fr/1999INPT035H.
Texto completoClauzier, Sébastien. "Conception et réalisation d'antennes intégrables en mâture pour les plateformes navales : applications aux communications V/UHF et à un radar de navigation à balayage électronique en bande X". Thesis, Rennes 1, 2013. http://www.theses.fr/2013REN1S067.
Texto completoThe need to communicate and detect potential enemies increases with the extension of maritime conflicts. This need impacts directly the number of antennas on naval platforms. However, this increase of aerials leads to several damaging effects: like coupling or high radar signature. To limit this effect, some companies have developed integrated mast design. This structure limits the coupling effect between aerials by a subdivision of the mast and provides an omnidirectional coverage for all antennas inserted inside the mast. The objective of the thesis is to design two antenna systems for the compact integrated mast (CmastTM) developed by the Constructions Mécanique de Normandie (CMN): a communication antenna in the V/UHF band and an electronically scanning antenna for a maritime navigation radar in X-band. For the communication in the V/UHF band, a broadband conical antenna has been developed (225-400MHz). This antenna provides an optimized radiation pattern to insure the communications between the ship and the aircrafts. An experimental validation has been done with a prototype. In the second study, we have developed an electronically scanning antenna for a navigation radar. This antenna is based on a transmit-array technology including an illuminating feed and an antenna which generates the appropriate radiation pattern. A large part of the study has been done on the feed, which illuminates an array with specific dimensions (1530mmx100mm). Three different near-field focusing feeds have been developed and some of them have been validated experimentally. Then, two architectures of transmit-array antennas have been studied, using two different technologies: printed technology and a mixed technology with waveguide and horn
Kaddour, Abdul sattar. "Antennes agiles pour la miniaturisation d’antenne large bande". Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT014/document.
Texto completoThese past years, the space sector is experiencing rapid growth (new players, new technologies) that tend to reduce the cost of telecom and observation applications via smaller satellites. In particular, reducing the size and weight of circularly polarized broadband antennas at VHF-UHF frequencies is a major challenge. However the miniaturization of an antenna is generally accompanied by a degradation of its efficiency and its bandwidth. In order to overcome this problem, the frequency agility technique constitutes an interesting solution to maintain the performance of the miniaturized antenna on a sub-band that can be driven on a wider frequency tuning range.The "crossed magneto-electric dipole" antenna based on the Huygens source concept is chosen for this work. Indeed, this antenna is part of the most compact broadband antennas with excellent unidirectional radiation. The first objective of this thesis is to study and develop original miniaturization techniques of the antenna. The second area of research focuses on the frequency agility of the miniature antenna initially developed to cover several octaves.Several miniaturization techniques such as geometric folding and capacitive loading were developed based on electromagnetic simulations, theoretical modeling and experiments. A frequency-reconfigurable compact VHF antenna is developed and realized. The thickness of the antenna is reduced to 0.09λ. The antenna covers a band from 94 MHz to 366 MHz thanks to only two tuning states (60% instant bandwidth for each). The broadside gain varies between 5 and 10 dBic over frequency with an axial ratio always lower than 2 dB
Ghannoum, Hassan. "Etude conjointe antenne/canal pour les communications Ultra Large Bande en présence du corps humain". Phd thesis, Télécom ParisTech, 2006. http://pastel.archives-ouvertes.fr/pastel-00002083.
Texto completoMello, 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.
Texto completoMetasurfaces 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
Luc, Jérôme. "Interaction des ondes éléctromagnétiques avec le vivant : étude et dosimétrie numérique de systèmes d'exposition aux fréquences microondes". Limoges, 2002. http://www.theses.fr/2002LIMO0059.
Texto completoIn front of the question of possible health effects of electromagnetic fields, and especially those that are caused by use of mobile phone, many research programs have begun in France and all over the world. Thus, this thesis is in the framework of the study of interaction of electromagnetic waves with the biological matter, and relates more precisely to numerical dosimetry. This one is made with an FDTD code. The study of head-phone interaction makes it possible to characterise the standard exposure of a cellular telephone. Thus, the need to use a realistic model of head, in order to take account of the heterogeneity of this last one, led us to realise a numerical model of head with MRI images. Before the dosimetric studies, evolutions have been brought to FDTD code and particular points have been studied: the excitation source, PML boundary condition and uncertainties of the SAR calculation. Then, the influence of the antenna and its position, like the phone position and the use of the hand-free kit, have been observed. The helix antenna is largely used in mobile telephony. To realise a dosimetric study of head-phone system with this antenna, an equivalent model, based on the self-inductive properties of the helix, has been developed. Concerning the exposure systems, we have been interested in a 'localised' system, with a loop antenna. In the framework of the COMOBIO project, French program of the RNRT, this system have been studied and it makes it possible to expose a rat under conditions which approach a standard exposure of cellular phones. At 900 MHz, the influence of the rat's model on the dosimetry of this system has been observed. Moreover, the adaptation of the system to the various frequencies of mobile telephony has been studied, like his dosimetry at 1800 MHz. A second system called 'whole body', using an horn antenna, has also been studied. The performances of those exposure systems have been compared with a plane wave illumination (device 'whole body') and carrousel (device 'head only')
Phan, Hong Phuong. "Conception d'antennes 2D et 3D sur des matériaux flexibles". Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT106/document.
Texto completoThe thesis was carried out within the ANR project « Stick’It » that aimed at developing new, low-cost and innovative technologies devoted to the design of 2D, 2,5D and 3D radiofrequency (RF) components including antennas printed on conformable materials. The targeted applications are primarily home-networking devices such as set-top boxes where their forms and dimensions are widely varied. Therefore, it is necessary to design antennas on flexible substrates.According to our needs for a substrate material that is flexible, low cost, with good RF properties, recycling ability, and especially ability to make 3D structures, after considering various dielectric materials for flexible electronics, paper substrate appeared to be the most suitable for our purpose.The work of this thesis conducted in three phases.In the first phase, it was the study of methods for characterization of materials to obtain their electromagnetic properties. After analysis, the method of perturbation using a cylindrical cavity was chosen for characterization of paper. The first results of this process were verified by realization and testing of simple antennas such as CPW-fed monopoles on paper and PET. Then, the measurement of E4D paper substrate was performed with 50 samples cut from various E4D paper sheets of three different thicknesses, 104 m, 210 m and 387 m. The results were analyzed statistically and gave r = 3.184, tan = 0.092.The dispersions of the results measured at 2.5 GHz are 0.25% for r and 0.26% for tan. These results were used for the next phase.In the second phase, different antennas were designed on 0.104-mm and 0.21-mm thick E4D paper including IFAs, SIW cavity-back antenna and microstrip-fed wideband monopole antennas. The prototypes were realized using screen printing technique and tested for matching property and radiation patterns.In the third phase the proposed antennas were studied in realistic package conditions, where a set-top box was made of ABS plastic with different dimensions. The first case was with two MIMO antennas orthogonally located in different ABS boxes with sufficient space, so that both of them can remain flat. The second case was a box with a restricted height, so that at least one of the antennas needs to be bent.Thus, a study of bending effect was carried out, first of all, with a simple straight dipole and a straight monopole on E4D paper, then with a wideband antenna proposed in the second phase. The study showed, that bending does not much affect the matching of the antenna over a wide frequency band. However, its radiation patterns rotate in the E-plane with a rotation angle depending on the bending location and bending angle.Then, the MIMO system of two antennas placed orthogonally in an ABS box with restricted height so that one antenna needed to be bent and another remained flat. In all cases of MIMO antenna system, we obtained good isolation (>20 dB) and Envelope Correlation Coefficient (ECC) less than 0.05
Lambard, Thomas. "Contribution à l'étude et la conception d'une antenne réseau à balayage électronique pour liaisons de données haut-débit entre un drone et un satellite en bande Ka". Toulouse 3, 2010. http://www.theses.fr/2010TOU30072.
Texto completoLow profile antennas will be important in future communications. Low profile phased array antennas allow to make easier the antenna integration and to shift the main beam over a wide area. At the same time, the increase of data rates and the saturation of classical frequency bands lead to operate data transmission at higher frequencies. The aim of this work is so the study, the design and the making of a phased array antenna for high data rate SATCOM on UAV (Unmanned Aerial Vehical) at 30 GHz. Firstly, the main characteristics of the phased array antenna have been defined. After, three printed antennas have been designed, made and measured, in order to have a wide scan phased array with a good circularly polarization. Phase shifters with varactor diodes have been also studied. The purpose is to minimize the insertion loss and to have a 360° phase shift. Finally, a phase array antenna has been designed, from the previous studies
Massiot, Jérôme. "Intégration de MEMS pour la réalisation d’ une antenne spirale à hautes performances reconfigurable". Thesis, Toulouse, INPT, 2013. http://www.theses.fr/2013INPT0100/document.
Texto completoThe evolution of radar and telecommunication systems needs antennas, which are able to adapt their performances in real time. Reconfigurable antennas can provides such characteristics through a reconfiguration of the frequency of operation, the polarisation or the radiation patterns. Besides, MEMS switches present attractive assets for reconfiguring a radiating element as they consume low power and have low losses. The thesis is about the integration of MEMS within an ultra wide band spiral antenna. The objectives of the thesis are: • To master the integration of packaged MEMS in an antenna • To reconfigure the spiral antenna for the achievement of a band rejection • To manufacture some prototypes and carry out experimental validations The radiation property of the spiral antenna has been studied. A reconfiguration of the spiral, which consists of inserting added elements within the radiating structure, has been investigated and applied. Spiral antennas with and without the reconfiguration mechanism have been manufatured and tested. The basic spiral antenna (without the reconfiguration mechanism) presents interesting properties: ultra wide band characteristics from 4 to 20 GHz, a relatively high gain of 5 to 9 dBi, and a low profile thickness of 3.5 mm. In practice, the achieved rejection has been difficult to prove due to the difficulties related to the integration of the packaged MEMS