• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 2
  • 1
  • Tagged with
  • 6
  • 6
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Conception d'antennes 2D et 3D sur des matériaux flexibles / Design of 2D and 3D antennas on flexible materials

Phan, Hong Phuong 15 November 2018 (has links)
Le travail de thèse a été réalisée dans le cadre du projet ANR «Stick’It» visant à développer de nouvelles technologies peu coûteuses et innovantes dédiées à la conception de composants radiofréquences (RF) 2D, 2,5D et 3D, notamment des antennes imprimées sur des matériaux conformes. Les applications ciblées sont principalement des appareils de réseaux domestique, tels que les décodeurs, dont les formes et les dimensions sont très variées. Par conséquent, il est nécessaire de concevoir des antennes sur des substrats souples.Selon nos besoins pour un matériau de substrat flexible, peu coûteux, avec de bonnes propriétés RF, la capacité de recyclage et en particulier la capacité à fabriquer des structures 3D, après avoir étudié différents matériaux diélectriques pour l’électronique flexible, le papier s'est trouvé le plus adapté.Les travaux de cette thèse se sont déroulés en trois phases.Dans la première phase, c'était l'étude des méthodes de caractérisation des matériaux pour obtenir leurs propriétés électromagnétiques. Après l'analyse, la méthode de perturbation utilisant une cavité cylindrique a été choisie pour la caractérisation du papier. Les premiers résultats de ce processus ont été vérifiés en réalisant et en testant des antennes simples telles que des monopoles alimentés par CPW sur du papier et du PET. Ensuite, la mesure du papier E4D a été effectuée avec 50 échantillons découpés dans différentes feuilles de papier E4D de trois épaisseurs différentes, 104 m, 210 m et 387 m. Les résultats ont été analysés statistiquement et ont donné r = 3.184, tan = 0.092. Les dispersions des résultats mesurés à 2,5 GHz sont 0.25% pour r et 0.26% pour tan. Ces résultats ont été utilisés pour la phase suivante.Au cours de la deuxième phase, les antennes différentes ont été conçues sur le papier E4D d'épaisseur 0,104 mm et 0,21 mm, notamment des IFA, des antennes SIW et des antennes monopoles alimentées par une ligne microruban. Les prototypes ont été réalisés à l'aide d'une technique de sérigraphie et testés pour déterminer les propriétés de l'adaptation et les diagrammes de rayonnement.Dans la troisième phase, les antennes proposées ont été étudiées dans des conditions d'emballage réalistes, où un boîtier décodeur était en plastique ABS avec différentes dimensions. Le premier cas concernait deux antennes MIMO placées orthogonalement dans des boîtiers ABS différents, avec un espace suffisant pour que les deux puissent rester plats. Le second cas était une boîte à hauteur limitée, de sorte qu’au moins une des antennes doit être pliée.Ainsi, une étude de l'effet de flexion a été réalisée, tout d'abord avec un simple dipôle droit et un monopole droit sur le papier E4D, puis avec une antenne à large bande proposée dans la seconde phase. L’étude a montré que la flexion n’affecte pas beaucoup l’adaptation de l’antenne sur une large bande de fréquences. Cependant, ses diagrammes de rayonnement tournent dans le plan E avec un angle de rotation dépendant de la position de pliage et de l'angle de flexion.Ensuite, le système MIMO de deux antennes placé orthogonalement dans un boîtier ABS de hauteur limitée, de sorte qu’une antenne doit être pliée et une autre reste plate. Dans tous les cas de système d'antenne MIMO, nous avons obtenu une bonne isolation (> 20 dB) et un coefficient de corrélation (ECC) inférieur à 0,05. / The 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.
2

Antenas para sistemas RFID impressas em substrato flexível. / Antennas for RFID systems printed on flexible substrate.

Robson Valmiro 12 February 2015 (has links)
Identificação de Dispositivos por Radiofrequência, do inglês, Radio Frequency Identification Device (RFID), é uma tecnologia para identificação, rastreamento e gerenciamento de produtos, animais e até mesmo pessoas sem a necessidade de um campo visual. Com o objetivo de alcançar custos menores e a utilização de processos de fabricação menos agressivo ao meio ambiente, tornou-se importante o desenvolvimento de novos tipos de etiquetas (tags). Em vista disso, a fabricação de antenas impressas compactas usando tinta condutiva, representa uma boa opção. O objetivo dessa pesquisa é o projeto e fabricação de antenas impressas sobre substratos flexíveis utilizando tinta condutiva composta de nanopartículas de prata. O desenvolvimento deste tipo de etiquetas é justificado principalmente pelos seguintes motivos. Primeiro, o processo reduz o uso de agentes químicos comumente empregados na fabricação convencional, levando a uma significativa redução no impacto ambiental. Segundo, a fabricação utilizando substratos como, por exemplo, papel ou polímero, reduz substancialmente o custo final da etiqueta. Estudos teóricos e práticos, juntamente com simulações eletromagnéticas foram realizados. Dois processos de prototipagem da etiqueta foram executados: um utilizando uma impressora jato de tinta que funciona propelindo gotas de tinta sobre o substrato e o outro utilizando serigrafia ou silkscreen printing que é muito prático para imprimir formas geométricas através de uma tela de fios trançados. Esses métodos de impressão permitiram a produção rápida da antena sem a necessidade de máscaras de fotolitografia, como é amplamente utilizado na indústria eletrônica. Quatro protótipos foram produzidos e medidas foram realizadas para verificar a viabilidade da utilização dessas etiquetas impressas em relação à sua operação, a confiabilidade das informações armazenadas e a troca de dados com o leitor RFID via interface aérea. Os resultados práticos foram comparados com os obtidos de etiquetas comerciais, onde foi possível verificar que a antena fabricada com tinta condutiva é capaz de capturar e radiar ondas eletromagnéticas de forma eficiente, resultando em uma troca de dados confiáveis através da interface aérea. / Radio Frequency Identification Device (RFID), it is a technology using electromagnetic waves for identifying, tracking and management of products, animals and even people without requiring a visual field. Aiming at achieving low costs and using less aggressive manufacturing processes to the environment, it has become important to develop new types of RFID tags. In view of that, manufacturing compact printed antennas using conductive ink represents a good option. The goal of this research is the design of printed antennas on flexible substrates using silver nanoparticles ink. The developing of this type of tags is justified mainly by the following reasons. First, the process reduces the use of chemical agents commonly employed in conventional manufacturing leading to a significant reduction of the environmental impact. Second, the fabrication using substrates such as paper and polymer foils, substantially reduces the final cost of the tags. Theoretical and practical studies along with electromagnetic simulations were conducted. Two process of RFID prototyping were performed: one using an inkjet printer that operates by propelling particles of conductive ink onto the substrate and another using silkscreen printing that is a very practical method to print geometric forms through a twisted wires screen. These technologies allowed fast production of the antenna without requiring photolithographic masks, as it is widely used in the electronics industry. Four prototypes were produced and measurements were taken to verify the feasibility of using RFID tags printed with conductive ink regarding to its operation, reliability of the stored information and the exchange of data with the RFID reader via air interface. Practical results were compared with those obtained of the commercial tags. It was possible to verify that the antenna manufactured with conductive ink was able to capture and radiate efficiently electromagnetic waves, resulting in reliable exchange of data with the reader through the air interface
3

Antenas para sistemas RFID impressas em substrato flexível. / Antennas for RFID systems printed on flexible substrate.

Valmiro, Robson 12 February 2015 (has links)
Identificação de Dispositivos por Radiofrequência, do inglês, Radio Frequency Identification Device (RFID), é uma tecnologia para identificação, rastreamento e gerenciamento de produtos, animais e até mesmo pessoas sem a necessidade de um campo visual. Com o objetivo de alcançar custos menores e a utilização de processos de fabricação menos agressivo ao meio ambiente, tornou-se importante o desenvolvimento de novos tipos de etiquetas (tags). Em vista disso, a fabricação de antenas impressas compactas usando tinta condutiva, representa uma boa opção. O objetivo dessa pesquisa é o projeto e fabricação de antenas impressas sobre substratos flexíveis utilizando tinta condutiva composta de nanopartículas de prata. O desenvolvimento deste tipo de etiquetas é justificado principalmente pelos seguintes motivos. Primeiro, o processo reduz o uso de agentes químicos comumente empregados na fabricação convencional, levando a uma significativa redução no impacto ambiental. Segundo, a fabricação utilizando substratos como, por exemplo, papel ou polímero, reduz substancialmente o custo final da etiqueta. Estudos teóricos e práticos, juntamente com simulações eletromagnéticas foram realizados. Dois processos de prototipagem da etiqueta foram executados: um utilizando uma impressora jato de tinta que funciona propelindo gotas de tinta sobre o substrato e o outro utilizando serigrafia ou silkscreen printing que é muito prático para imprimir formas geométricas através de uma tela de fios trançados. Esses métodos de impressão permitiram a produção rápida da antena sem a necessidade de máscaras de fotolitografia, como é amplamente utilizado na indústria eletrônica. Quatro protótipos foram produzidos e medidas foram realizadas para verificar a viabilidade da utilização dessas etiquetas impressas em relação à sua operação, a confiabilidade das informações armazenadas e a troca de dados com o leitor RFID via interface aérea. Os resultados práticos foram comparados com os obtidos de etiquetas comerciais, onde foi possível verificar que a antena fabricada com tinta condutiva é capaz de capturar e radiar ondas eletromagnéticas de forma eficiente, resultando em uma troca de dados confiáveis através da interface aérea. / Radio Frequency Identification Device (RFID), it is a technology using electromagnetic waves for identifying, tracking and management of products, animals and even people without requiring a visual field. Aiming at achieving low costs and using less aggressive manufacturing processes to the environment, it has become important to develop new types of RFID tags. In view of that, manufacturing compact printed antennas using conductive ink represents a good option. The goal of this research is the design of printed antennas on flexible substrates using silver nanoparticles ink. The developing of this type of tags is justified mainly by the following reasons. First, the process reduces the use of chemical agents commonly employed in conventional manufacturing leading to a significant reduction of the environmental impact. Second, the fabrication using substrates such as paper and polymer foils, substantially reduces the final cost of the tags. Theoretical and practical studies along with electromagnetic simulations were conducted. Two process of RFID prototyping were performed: one using an inkjet printer that operates by propelling particles of conductive ink onto the substrate and another using silkscreen printing that is a very practical method to print geometric forms through a twisted wires screen. These technologies allowed fast production of the antenna without requiring photolithographic masks, as it is widely used in the electronics industry. Four prototypes were produced and measurements were taken to verify the feasibility of using RFID tags printed with conductive ink regarding to its operation, reliability of the stored information and the exchange of data with the RFID reader via air interface. Practical results were compared with those obtained of the commercial tags. It was possible to verify that the antenna manufactured with conductive ink was able to capture and radiate efficiently electromagnetic waves, resulting in reliable exchange of data with the reader through the air interface
4

Etude et conception d'un capteur-RFID passif en bande UHF : application à l'agroalimentaire / Study and design of the passive RFID-SENSOR in the UHF band : application to agrifood diagnosis

Belaizi, Yassin 30 November 2018 (has links)
La technologie d’identification radiofréquence (RFID) se décline aujourd’hui dans des milliers d’applications. Parmi elles nous pouvons citer les applications de gestion logistique des palettes/cartons dans les entrepôts industriels (RFID UHF) ainsi que l’identification des abonnés dans les réseaux de transports urbains (RFID HF). Depuis quelques années, des contributions scientifiques autour des technologies d’identification radiofréquence (RFID) avec un couplage capteur sont de plus en plus visibles. L’intérêt grandissant pour ce type de technologie s’appuie sur la possibilité d’une utilisation en masse de capteurs bon marchés pouvant être intégrés sur chaque objet. On parle alors d’objet connecté ou d’internet des objets (IoT). Dans cette thèse, nous nous focalisons sur l’étude et le développement d’un capteur RFID passif fonctionnant en bande UHF. Cette orientation technologique est dictée par l’application visée, l’agro-alimentaire, qui requiert des coûts de fabrication les plus faibles possibles et une distance de lecture supérieure au mètre. Pour l’élément sensible, nous utilisons un bio-polymère, plus précisément le gluten de blé dont les propriétés diélectriques en fonction de l’humidité relative ont été étudiées précédemment. Nous nous attachons à traiter toutes les problématiques liées à la communication entre un lecteur et un capteur RFID passif, l’objectif ultime de cette thèse étant de récupérer une information capteur à l’aide d’un lecteur RFID conventionnel respectant les standards du domaine et les directives radio en vigueur dans les différentes régions du monde. Pour valider cette étude, nous mettons en œuvre des capteurs-RFID pour réaliser un démonstrateur d’emballage « intelligent » permettant le suivi de la qualité des aliments. / Radio frequency identification (RFID) technology is available today in thousands of applications. Among them we can mention the logistics management applications pallets / cardboard in industrial warehouses (RFID UHF) and the identification of subscribers in urban transport networks (RFID HF). In recent years, scientific contributions around the radio frequency identification (RFID) technologies with a sensor coupling are increasingly visible. The growing interest in this type of development rely heavily on a mass use of inexpensive sensors that can be integrated on each object.It is calledconnected objects or Internet of Things (IoT). In this thesis, we focus on the study and development of a passive RFID sensor operating in UHF band. This technological orientation is dictated by the targeted application, the food industry, which requires the lowest possible manufacturing costs and a reading distance greater than one meter. For the sensitive element, we use a biopolymer, specifically wheat gluten whose dielectric properties as a function of relative humidity have been studied previously. We are committed to dealing with all the issues related to the communication between a reader and a passive RFID sensor, the ultimate objective of this thesis being to get a sensor information using a conventional RFID reader complying with the standards and the radio directives imposed in different regions of the world. To validate this study, we are implementing RFID sensors to create a smart packaging demonstrator for monitoring the quality of food.
5

Conception d'antennes souples et de conducteurs magnétiques artificiels en bande UHF / Design of flexible antennas and of artificial magnetic corductors in UHF band

Presse, Anthony 08 December 2015 (has links)
L'invention de l'antenne fût à la base de la création des communications sans fil à l'orée du XXe siècle. A l'origine des objets métalliques destinés à transmettre et recevoir des ondes électromagnétiques, les antennes n'ont cessé de se complexifier pour satisfaire l'impressionnant développement des communications sans fil. C'est dans ce contexte qu'est né le concept d'antenne « wearable » il y a moins de deux décennies ouvrant un nouveau champ de recherche sur les antennes souples. C'est dans ce cadre que ce travail de thèse se consacre à la conception d’antennes souples en bande UHF.Une première étude a permis de concevoir une antenne Vivaldi antipodale [150 - 900 MHz] souple pour la Section Technique de l'Armée de Terre. Six de ces antennes sont destinées à être placées sous un ballon gonflé à l'hélium pour réceptionner des signaux RF.Une seconde étude est effectuée en collaboration avec la société Syrlinks et le CNES. L'objectif du projet est de concevoir des antennes souples pour le suivi de personnes avec le système ARGOS (401 et 466 MHz). La solution retenue est une PIFA planaire de largeur inférieure à lambda/3. Elle a l'avantage d'être fine et légère. Le matériau souple employé est un caoutchouc silicone sélectionné parmi plusieurs matériaux souples grâce à des caractérisations diélectriques. Cependant, le problème de cette antenne est qu'elle possède un rayonnement quasi-omnidirectionnel. Etant donné qu'il n'était pas envisageable d'utiliser un plan réflecteur métallique pour des raisons de dimensions, il a été décidé de concevoir un conducteur magnétique artificiel (CMA) souple. Toutefois, la conception de CMA dans le bas de la bande UHF se heurte à des difficultés de miniaturisation. Pour contourner ce problème, il a été développé deux concepts de CMA à cellules unitaires de faibles dimensions devant la longueur d'onde. La première solution utilise des capacités interdigitées et la seconde une structure double couche. Pour ces deux concepts, un modèle circuit est proposé et validé par des mesures expérimentales. Les mesures de l'association CMA - antenne montrent une bande passante suffisante pour des applications ARGOS et un rayonnement majoritairement dirigée dans la direction opposé à celle du CMA. / The invention of antennas was the base of wireless communications appearance at the dawn of the twentieth century. Originally metal objects for transmitting and receiving electromagnetic waves, antennas have steadily become more complex to meet the impressive development of wireless communications. It is in this context that the concept of wearable antennas was born less than two decades ago opening a new field of research namely flexible antennas. It is in this framework that this thesis is dedicated to the design of flexible antennas for UHF band.A first study enabled the design of a flexible antipodal Vivaldi antenna [150-900 MHz] for Technical Section of the Army. Six of these antennas are intended to be placed under a balloon inflated with helium for receiving RF signals.A second study was conducted in collaboration with the company Syrlinks and CNES. The objective of the project is to design flexible antennas for tracking people with ARGOS system (401 and 466 MHz). The selected solution is a planar PIFA which width is smaller than lambda/3. This antenna has the advantage of being thin and light. The flexible material used is a silicone rubber and it was selected among several others due to some dielectric characterizations. However, the drawback of this antenna is that it has a quasi-omnidirectional radiation pattern. Since it was not possible to use a reflector metal plane due to size constraints, it was decided to design a flexible artificial magnetic conductor (AMC). However, the design of AMCs in the lower UHF band is challenged with the miniaturization difficulties. Two concepts of small size (compared to the wavelength) AMCs unit cells were developed to work around this problem. The first solution uses interdigitated capacitors and the second a double layer structure. For these two concepts, a circuit model is proposed and validated by experimental measurements. The measurement of the AMC associated antenna demonstrates a bandwidth sufficient for ARGOS applications and a radiation pattern mostly directed in the direction opposite to that of the AMC.
6

Integration and miniaturization of antennas for system-on-package applications

Altunyurt, Nevin 05 April 2010 (has links)
Wireless communications have been an indispensable aspect of everyday life, and there is an increasing consumer demand for accessing several wireless communication technologies from a single, compact, mobile device. System-on-package (SOP) technology is an advanced packaging technology that has been proven to realize the convergence of multiple functions into miniaturized, high-performance systems to meet this demand. With the advancements in the SOP technology, the miniaturization of the front-end module has been achieved using embedded passives in multilayer packages. However, the integration of the antenna directly on the module package is still the barrier to achieve a fully-integrated, high-performance RF SOP system. The main reason for this missing link is that integrating the antenna on the package requires miniaturizing the antenna, which is a difficult task. The focus of this dissertation is to design high-performance antennas along with developing techniques for miniaturization and system-on-package (SOP) integration of these antennas to achieve fully-integrated SOP systems using advanced multilayer organic substrates and thin-film magneto-dielectric materials. The targeted spectrum for the antenna designs are 2.4/5 GHz WLAN/WiMAX and 60 GHz WPAN bands. Several novel antenna designs and configurations to integrate the antenna on the package along with the module are discussed in this dissertation. The advanced polymers used in this research are Liquid Crystalline Polymer (LCP), RXP, and thin-film magneto-dielectrics.

Page generated in 0.0841 seconds