La prévision des phénomènes de pollution atmosphérique est l'objectif central de la campagne ESCOMPTE-2001, qui s'est déroulée durant l'été 2001 dans la région très hétérogène de Marseille/Fos/Berre. Cet objectif nécessite une bonne compréhension et prise en compte, par les modèles numériques de physico-chimie, des processus physiques intervenant dans la Couche Limite Atmosphérique (CLA), au sein de laquelle s'effectuent le transport et la diffusion des polluants émis en surface.<br />Dans le cadre de la campagne ESCOMPTE-2001, ce travail de thèse est consacré à l'étude de la basse troposphère en période de brise de mer, situation météorologique défavorable à la qualité de l'air des zones côtières. Il a permis notamment de mettre en évidence une oscillation de l'intensité de la brise de mer et des compétitions de brises de mer locales et régionales, qui modifient le temps d'advection de l'air marin sur la surface terrestre et ont donc des répercussions importantes sur le développement de la CLA et sa concentration en polluants. Ces travaux s'appuient principalement sur le réseau de quatre radars profileurs de vent UHF mis en place sur la zone côtière de Marseille/Fos/Berre, permettant une description en trois dimensions et en continu dans le temps des écoulements de brises de mer et de la CLA.<br />Pour les besoins de cette étude phénoménologique, des développements méthodologiques sont apportés sur la mesure des propriétés turbulentes de la CLA par les radars UHF (termes du bilan de l'énergie cinétique turbulente) et sur leur utilisation en réseau pour l'étude de la trajectographie de panaches de polluants.

Les régimes dynamiques dans les basses couches de l'atmosphère à l'île de la Réunion sont conditionnés par l'action du relief et du rayonnement sur l'écoulement synoptique. L'île est située en permanence dans le flux des alizés de sud-est et son relief élevé, culminant à 3000 m dans le centre de l'île et 2600 m au sud, constitue un obstacle important pour l'écoulement moyen. Le relief, le chauffage différentiel des pentes et le contraste thermique avec l'océan influent sur les échanges locaux entre la couche limite marine et la troposphère libre.L'analyse des phénomènes complexes de l'écoulement atmosphérique au niveau de l'île a pour but initial de caractériser les transferts de polluants émis localement. Cette étude a deux applications : * La première rentre dans le cadre préparatoire à la mise en place, à 2200 m d'altitude sur le Piton Maïdo, de l'observatoire atmosphérique de l'OPAR, à l'horizon 2011. L'objectif est de comprendre les circulations locales induites par le relief et les transports associés afin de discriminer d'éventuelles pollutions par les sources locales sur le signal qui sera mesuré in situ au sommet du Maïdo.* La seconde vise à étudier la diffusion des panaches volcaniques du Piton de la Fournaise. L'éruption majeure d'avril 2007 du volcan réunionnais a montré que des panaches pouvaient générer d'importantes pollutions dans diverses parties de l'île allant jusqu'à poser de réels problèmes environnementaux et de santé publique.Ces applications s'appuient sur une étude par modélisation numérique à haute résolution des écoulements atmosphériques dans les basses couches au niveau de l'île, au moyen du modèle météorologique de recherche MésoNH, permettant de conduire un ensemble de simulations sur cas idéalisés puis sur cas réels avec diffusion de traceurs passifs.

RFID has been characterized as a “disruptive technology” that has the potential to revolutionize numerous key sectors. A key advantage of passive RFID applications is the ability to wirelessly transmit automatic identification and related information using very little power. This paper presents an experimental investigation to inform the optimal configuration for programming passive ultra-high frequency (UHF) RFID media in dynamic applications. Dynamic programming solutions must be designed around the tag’s functionality, the physical programming configuration and environment. In this investigation, we present a methodology to determine an optimal configuration to maximize the systems programming efficiency for dynamic applications.

This thesis investigates inkjet-printed flexible antennas fabricated on paper substrates as a system-level solution for ultra-low-cost and mass production of RF structures. These modules are designed for the UHF Radio Frequency Identification (RFID) Tags and Wireless Sensor Nodes (WSN); however the approach could be easily extended to other microwave and wireless applications. Chapter 1 serves as an introduction to RFID technology and its capabilities while listing the major challenges that could potentially hinder RFID practical implementation. Chapter 2 discusses the benefits of using paper as a substrate for high-frequency applications, reporting its very good electrical/dielectric performance up to at least 1 GHz. The dielectric properties are studied by using the microstrip ring resonator. Brief discussion on Liquid Crystal Polymer (LCP) is also given in this chapter. Chapter 3 gives details about the inkjet printing technology, including the characterization of the conductive ink, which consists of nano-silver-particles, while highlighting the importance of this technology as a fast and simple fabrication technique especially on flexible organic (e.g.LCP) or paper-based substrates. Chapter 4 focuses on antenna designs. Four examples are given to provide: i) matching techniques to complex IC impedance, ii) proof of concept of inkjet printing on paper substrate through measurement results, iii) demonstration of a fully-integrated wireless sensor modules on paper and show a 2D sensor integration with an RFID tag module on paper. Chapter 5 concludes the thesis by explaining the importance of this work in creating a first step towards an environmentally friendly generation of "green" RF electronics and modules.

Os sistemas de identificação por radio frequências (RFID - Radio Frequency IDentification) são uma tecnologia de transmissão e armazenamento de informação remota, composta por dispositivos (etiquetas e leitores RFID), que comunicam à distância sem necessitarem de qualquer contato direto. Embora a RFID possua algumas décadas de existência, apenas nos últimos anos tem recebido atenção por parte do meio industrial e demonstrado ser uma tecnologia com um futuro promissor, devido especialmente às suas inúmeras possibilidades de utilização e vantagens que possui quando comparada com outras tecnologias semelhantes. Embora a utilização da RFID aparente ser bastante vantajosa e com bastantes benefícios, muitas questões e dificuldades são colocadas no momento da sua implementação. No âmbito desta dissertação será apresentado uma revisão bibliográfica sobre o estado de arte da tecnologia RFID, os dispositivos que a compõem e que são essenciais ao seu funcionamento, assim como várias aplicações da tecnologia. Serão igualmente abordados os problemas que dificultam a disseminação da tecnologia. O objetivo do trabalho foi (i) realizar um levantamento na literatura dos fatores que influenciam a eficiência da tecnologia RFID e (ii) realizar uma análise experimental dos fatores que influenciam a capacidade de transmissão do sinal de radio frequência entre os vários dispositivos RFID existentes no contexto industrial. / The Radio frequency identification (RFID) systems are a technology that permits the transmission and storage of information remotely, composed of devices (tags and readers), which communicate at a distance without the need for any direct contact. While RFID has a few decades of existence only in recent years it has received attention from the industrial environment and demonstrated to be a technology with a promising future, especially due to its many possibilities of use and advantages when compared with other similar technologies. However, although the actual use of RFID may appear to be very advantageous and with many benefits, many issues and problems are posed at time of implementation. Within this dissertation it will be presented a literature review on the state of the art RFID technology, the devices that make up to it and that are essential to its operation, as well as the various applications of technology. The problems and difficulties that are posed at the moment and difficulties that compromise the spread of technology will also be discussed. The objective of this work was (i) to conduct a literature review of the factors that influence the efficiency of RFID technology and (ii) conduct an experimental analysis of the factors that influence the ability of signal transmission between different radio frequency RFID devices existing in the industrial context.

Os sistemas de identificação por radio frequências (RFID - Radio Frequency IDentification) são uma tecnologia de transmissão e armazenamento de informação remota, composta por dispositivos (etiquetas e leitores RFID), que comunicam à distância sem necessitarem de qualquer contato direto. Embora a RFID possua algumas décadas de existência, apenas nos últimos anos tem recebido atenção por parte do meio industrial e demonstrado ser uma tecnologia com um futuro promissor, devido especialmente às suas inúmeras possibilidades de utilização e vantagens que possui quando comparada com outras tecnologias semelhantes. Embora a utilização da RFID aparente ser bastante vantajosa e com bastantes benefícios, muitas questões e dificuldades são colocadas no momento da sua implementação. No âmbito desta dissertação será apresentado uma revisão bibliográfica sobre o estado de arte da tecnologia RFID, os dispositivos que a compõem e que são essenciais ao seu funcionamento, assim como várias aplicações da tecnologia. Serão igualmente abordados os problemas que dificultam a disseminação da tecnologia. O objetivo do trabalho foi (i) realizar um levantamento na literatura dos fatores que influenciam a eficiência da tecnologia RFID e (ii) realizar uma análise experimental dos fatores que influenciam a capacidade de transmissão do sinal de radio frequência entre os vários dispositivos RFID existentes no contexto industrial. / The Radio frequency identification (RFID) systems are a technology that permits the transmission and storage of information remotely, composed of devices (tags and readers), which communicate at a distance without the need for any direct contact. While RFID has a few decades of existence only in recent years it has received attention from the industrial environment and demonstrated to be a technology with a promising future, especially due to its many possibilities of use and advantages when compared with other similar technologies. However, although the actual use of RFID may appear to be very advantageous and with many benefits, many issues and problems are posed at time of implementation. Within this dissertation it will be presented a literature review on the state of the art RFID technology, the devices that make up to it and that are essential to its operation, as well as the various applications of technology. The problems and difficulties that are posed at the moment and difficulties that compromise the spread of technology will also be discussed. The objective of this work was (i) to conduct a literature review of the factors that influence the efficiency of RFID technology and (ii) conduct an experimental analysis of the factors that influence the ability of signal transmission between different radio frequency RFID devices existing in the industrial context.

Os sistemas de identificação por radio frequências (RFID - Radio Frequency IDentification) são uma tecnologia de transmissão e armazenamento de informação remota, composta por dispositivos (etiquetas e leitores RFID), que comunicam à distância sem necessitarem de qualquer contato direto. Embora a RFID possua algumas décadas de existência, apenas nos últimos anos tem recebido atenção por parte do meio industrial e demonstrado ser uma tecnologia com um futuro promissor, devido especialmente às suas inúmeras possibilidades de utilização e vantagens que possui quando comparada com outras tecnologias semelhantes. Embora a utilização da RFID aparente ser bastante vantajosa e com bastantes benefícios, muitas questões e dificuldades são colocadas no momento da sua implementação. No âmbito desta dissertação será apresentado uma revisão bibliográfica sobre o estado de arte da tecnologia RFID, os dispositivos que a compõem e que são essenciais ao seu funcionamento, assim como várias aplicações da tecnologia. Serão igualmente abordados os problemas que dificultam a disseminação da tecnologia. O objetivo do trabalho foi (i) realizar um levantamento na literatura dos fatores que influenciam a eficiência da tecnologia RFID e (ii) realizar uma análise experimental dos fatores que influenciam a capacidade de transmissão do sinal de radio frequência entre os vários dispositivos RFID existentes no contexto industrial. / The Radio frequency identification (RFID) systems are a technology that permits the transmission and storage of information remotely, composed of devices (tags and readers), which communicate at a distance without the need for any direct contact. While RFID has a few decades of existence only in recent years it has received attention from the industrial environment and demonstrated to be a technology with a promising future, especially due to its many possibilities of use and advantages when compared with other similar technologies. However, although the actual use of RFID may appear to be very advantageous and with many benefits, many issues and problems are posed at time of implementation. Within this dissertation it will be presented a literature review on the state of the art RFID technology, the devices that make up to it and that are essential to its operation, as well as the various applications of technology. The problems and difficulties that are posed at the moment and difficulties that compromise the spread of technology will also be discussed. The objective of this work was (i) to conduct a literature review of the factors that influence the efficiency of RFID technology and (ii) conduct an experimental analysis of the factors that influence the ability of signal transmission between different radio frequency RFID devices existing in the industrial context.

No description available.

This thesis deals with RFID tags. In the first part of the thesis, the general overviews of the present-day RFID systems are presented. This part of the thesis is focused on the passive back-scatter UHF tags and the advantages of their application in supply chain usage. Subsequently, the electromagnetic simulators CST Microwave Studio and IE3D Zeland are described. These simulators were used to design loaded meander antennas. The antennas were designed for different materials and frequency bands of 867 MHz and 2.4 GHz. The designed antennas were made without as well as with the reflector which allows using the antennas in the vicinity of metals. Produced antennas were experimentally tested in the company METRA Blansko Inc, where one of the most significant characteristics of passive RFID tags – the read range was observed.

The object of this master's thessis is study and description of RF circuits, which are used for receiveing. This work is also aimed to design this circuits and their simulation in Ansoft Designer software. Focus is placed to the standard parameters of receiving technology. The description of amplifier design is presented in this work. Parameters of this amplifier are optimalized to low noise figure. Frequency multiplier designs are included in this project.