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  • 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.
121

Elevando a capacidade de integração de sistemas de Middleware RFID através do processamento de eventos complexos distribuídos entre diferentes organizações e negócio

Amaral, Leonardo Albernaz January 2011 (has links)
Made available in DSpace on 2013-08-07T18:43:15Z (GMT). No. of bitstreams: 1 000433739-Texto+Completo-0.pdf: 4343120 bytes, checksum: 6fb5a96a4ec12d9cbad8c22e5910447a (MD5) Previous issue date: 2011 / Over the years the RFID technology has become an area of research and development extremely challenging and rapidly expanding. Although there are sophisticated RFID software systems, many of these systems are based on RFID middleware technologies with basic data management features according to specifications of the EPCglobal ALE (Application Level Events). These features of the ALE act as an integration layer between raw RFID data (data without prior processing) and the application logic. No business semantics is expressed in this layer, which hinders the contextualization of events. This problem is considered a technological gap of RFID middleware systems that are based on the specifications of the ALE. Beyond the limitations of conventional mechanisms for data management of RFID events, existing specifications for RFID software technology (EPC Network according to EPCglobal) present challenges in the services proposed to integrate and share events among different business organizations (ONS, EPCIS and DS). Such services do not allow the use of indirect methods of event communication, which hinders the detection of distributed complex events. This paper presents an RFID software framework whose goal is to raise the interorganizational integration capability of RFID middleware systems. The systems integration is made through mechanisms of CEP (Complex Event Processing) that cooperate using event notification services. CEP technology is integrated with an RFID middleware system that implements the ALE specification. The framework is based on the concept of CEP network for processing and notification of distributed complex events. Each processing node has its own mechanism of CEP and the cooperation between nodes provides a system of global business rules, which allows the decomposition and execution of rules in different organizations. This work is important because besides identify limitations of current RFID software technologies, experimental results of the proposed framework show that the approaches used in the framework improve project and development activities of RFID applications maintaining acceptable levels of performance of the CEP engine used. When compared with other RFID systems, the framework provides several enhancements and complies with key requirements for both management and integration of RFID event data. Moreover, the framework adds new features for integration, management and sharing of RFID event data. / Com o passar dos anos a tecnologia RFID se tornou uma área de pesquisa e desenvolvimento extremamente estimulante e de rápida expansão. Embora existam sofisticados sistemas de software para RFID, muitos destes sistemas existentes estão baseados em tecnologias de middleware RFID com funcionalidades básicas de gerenciamento de dados de acordo com especificações do ALE (Eventos no Nível de Aplicação) segundo a EPCglobal. Estas funcionalidades do ALE agem como uma camada de integração entre dados RFID brutos (sem prévio processamento) e a lógica da aplicação. Nenhuma semântica de negócio é expressada nesta camada o que dificulta a contextualização de eventos. Este problema é considerado um gap tecnológico inerente às plataformas de middleware RFID que estão baseadas nas especificações do ALE. Além das limitações dos mecanismos convencionais para gerenciamento de dados de eventos RFID, especificações existentes para tecnologias de software RFID (EPC Network segundo a EPCglobal) apresentam desafios nos serviços propostos para integração e compartilhamento de eventos entre diferentes organizações de negócio (ONS, DS e EPCIS). Tais serviços não permitem a utilização de esquemas de comunicação indireta de eventos o que dificulta a detecção de eventos complexos distribuídos. Este trabalho apresenta um framework de software RFID cujo objetivo é elevar a capacidade de integração interorganizacional de sistemas de middleware RFID através de mecanismos de CEP (Processamento de Eventos Complexos) que cooperam entre si por meio de serviços de notificação de eventos. A tecnologia CEP é integrada a um sistema de middleware RFID que implementa especificações do ALE. O framework baseia-se no conceito de rede de CEPs para processamento e notificação de eventos complexos distribuídos. Cada nodo de processamento envolvido tem seu próprio mecanismo de CEP e a cooperação entre nodos provê um sistema de regras de negócio global que permite a decomposição e execução de regras de negócio em diferentes organizações. Este trabalho é importante, pois, além de identificar limitações e problemas das tecnologias atuais de software RFID, resultados experimentais obtidos através de testes do framework proposto demonstram que as abordagens utilizadas na construção do framework melhoram atividades de projeto e desenvolvimento de aplicações RFID mantendo níveis aceitáveis de desempenho do mecanismo de CEP utilizado. Quando comparado com os principais sistemas RFID existentes, o framework apresenta melhorias e cumpre com os principais requisitos, tanto de gerenciamento quanto de integração de dados de eventos RFID. Além disso, o framework agrega novas funcionalidades para integração, gerenciamento e compartilhamento de dados de eventos RFID.
122

Approches logicielles de sûreté de fonctionnement pour les systèmes RFID / Software dependability approches for RFID systems

Kheddam, Rafik 09 April 2014 (has links)
On assiste de nos jours à une utilisation croissante des systèmes RFID (Radio Frequency IDentification systems) dans diversdomaines d’application (logistique, systèmes de production, inventaires, traçabilité, etc.). Certaines de ces applicationsprésentent un caractère critique à l’image du respect de la chaîne de froid lors de l’acheminement de denrées alimentaires oudans le cas de systèmes de manutention de bagages dans les aéroports. Or, la sensibilité des systèmes RFID vis-à-vis de leurenvironnement, notamment des perturbations électromagnétiques ou de la présence d’obstacles, les rend vulnérables. Demême, de par le nombre important d’éléments (étiquettes, lecteurs) mis en oeuvre dans de tels systèmes, des comportementserronés peuvent survenir en raison de fautes dans les divers éléments constituant le système. D’où l’importance et la nécessitéde traiter le problème de la sûreté de fonctionnement et de la tolérance aux fautes dans le but de rendre ces systèmes plusrobustes.L’objectif de cette thèse concerne la proposition d’approches logicielles de test et de diagnostic en ligne adaptées aux systèmesRFID en vue d’améliorer leur robustesse. Depuis quelques années, une exploitation efficace des systèmes RFID a vu ledéveloppement d’intergiciels ou de middlewares RFID, dont le rôle est de proposer des services permettant la gestion desquantités de données importantes en provenance des lecteurs RFID. L’utilisation de tels intergiciels est d’un grand intérêt pourla sûreté de fonctionnement des systèmes RFID en raison de la nature distribuée de ces systèmes ; en particulier, grâce àl’intégration des mécanismes de sûreté de fonctionnement, plus précisément le test et le diagnostic en ligne, au niveau dumiddleware. Dans cette thématique, nous avons proposé plusieurs solutions pour couvrir les deux couches centrales du systèmeà savoir la couche middleware et son interface de communication avec les sources de données, le protocole LLRP (Low LevelReader Protocol). Nous avons proposé une solution middleware compatible avec le standard de communication des systèmesRFID, et utilisée comme un réceptacle pour une solution algorithmique de diagnostic probabiliste qui permet de détecter lesdéfaillances potentielles des composants du système sur la base d’un modèle probabiliste qui tient compte de l’environnementd’exécution. Ensuite, nous avons proposé un mécanisme d’analyse des fichiers log de l’interface de communication LLRP,complémentaire à l’algorithme probabiliste et qui permet d’approfondir le diagnostic en recherchant les causes de la défaillancedétectée sur la base de différentes signatures de défaillances déjà établies. Enfin, nous avons proposé une extension dustandard de communication LLRP qui tient compte de plusieurs comportements défaillants dans le but de rendre ce dernier plusfiable. / We are witnessing today a growing use of RFID (Radio Frequency IDentification) systems in various application areas (logistics,production systems, product traceability, etc.). Some of these applications are critical such as food-related cold chain logistics orbaggage handling systems in airports. Nevertheless, RFID are very sensitive to their environment, including electromagneticdisturbances or presence of obstacles, making them error-prone. Also, because of the large number of elements (tags, readers,and sensors) constituting current RFID systems, erroneous behaviors are more frequent. Hence, it is important to address all theproblems related to RFID system dependability and deal with them in order to make these systems more robust.The goal of this thesis is the development of software test and online diagnosis facilities for RFID systems to improve theirrobustness. In recent years, the effective use of RFID systems has seen the development of RFID middleware solutions, whoserole is to provide services for the management of large amounts of raw data of the various RFID sources. Due to the distributednature of current RFID systems, the use of such solutions is of great interest regarding the improvement of RFID systemdependability. In particular, thanks to the integration of dependability mechanisms, specifically the online test and diagnosisapproaches in the RFID middleware solution. In addition, because of the middleware is considered as the backbone of an RFIDsystem, whereby the whole RFID dataflow passes; all the needed information will be availabe to our proposed approaches toperform a correct diagnosis. We proposed several solutions to cover the two main layers of RFID systems; namely, themiddleware layer and the communication layer between the middleware and the data sources, the Low Level Reader Protocol(LLRP). We have proposed a LLRP compliant middleware solution, used to accommodate a probabilistic diagnosis algorithm todetect potential failures of the RFID system components on the basis of a probabilistic model that takes into account theexecution conditions. Then, we proposed a complementary mechanism to the previous algorithm for analyzing the log files ofthe LLRP communication interface allowing further analysis by looking for the causes of the detected failures on the basis of an already defined set of failure signatures. Finally, we proposed an extension of the LLRP standard to make it more reliable bytaking into account several RFID failures.
123

Sistema híbrido de localização indoor baseado em RFID e análise visual

Berz, Everton Luís January 2015 (has links)
Made available in DSpace on 2015-06-30T02:06:11Z (GMT). No. of bitstreams: 1 000471311-Texto+Completo-0.pdf: 3539731 bytes, checksum: 45f5e399fc56af2961d60689146cd5df (MD5) Previous issue date: 2015 / Systems need to know the physical location of objects and people in order to improve the user experience and solve logistic and security problems. This work proposes a hybrid indoor positioning system based on passive RFID and visual analysis. The system focuses on bidimensional and tridimensional space localization of stationary objects with centimeter level accuracy. Also, off-the-shelf equipment are employed as sensor devices. By using RFID technology, machine learning approaches based on Artificial Neural Networks (ANN) and Support Vector Regression (SVR) are proposed. A Computer Vision (CV) subsystem detects visual markers in the scenario to enhance RFID localization. In order to combine RFID and optical technologies, we propose a novel sensor fusion method based on Multiple Region of Interest (MROI) and k-means technique. A multi-frequency method is proposed aimed to allow and improve the localization when using off-the-shelf equipment. We have implemented our system and evaluated it using real experiments. First, a performance benchmark was made in order to evaluate RFID antennas and tags positioning. Regarding to overall system performance, the localization error was between 9 and 33 cm under a 2D scenario. On this dimension, ANN performed 30% better than RNA approach. In comparison to RFID-only approach results, the hybrid system had improved by 32%. Three-dimensional space localization had a 63 cm accuracy in best case scenario. / Com o objetivo de otimizar a experiência do usuário e resolver problemas de logística e segurança, aplicativos necessitam conhecer a localização física de objetos e pessoas. As propostas de sistemas de localização para ambientes internos (indoor) baseados em somente uma tecnologia não vêm obtendo bom desempenho na localização, principalmente devido a limitações em relação às características interferentes presentes em ambientes internos. Este trabalho tem como objetivo o desenvolvimento de um sistema híbrido de localização indoor, capaz de obter a localização bidimensional e tridimensional de objetos estáticos, com precisão de poucos centímetros, utilizando equipamentos já estabelecidos no mercado. A partir do uso da tecnologia RFID, a localização é estimada através de modelos de aprendizado de máquina.São avaliados modelos baseados em Redes Neurais Artificiais (RNA) e Support Vector Regression (SVR). Um subsistema de visão computacional detecta marcadores visuais no cenário a fim de aprimorar a localização. Visando combinar as tecnologias RFID e óptica, é definido um método de fusão de sensores baseado em múltiplas regiões de interesse a partir da técnica k-means. Além disso, um método de multi-frequência é proposto com o objetivo de permitir e otimizar o uso do sistema em equipamentos off-the-shelf. O sistema foi implementado e avaliado em experimentos de laboratório. Inicialmente, foi analisado o desempenho do sistema em relação ao posicionamento de antenas e etiquetas RFID presentes no ambiente. Na avaliação geral do sistema sob escalabilidade 2D, o erro de localização se manteve entre 9 e 33 cm. Nesta dimensão, o modelo RNA superou o SVR em 30%. Na comparação entre o sistema híbrido e o emprego somente da tecnologia RFID, a fusão de sensores melhorou a precisão em aproximadamente 32%. Em escalabilidade tridimensional, a precisão foi de 63 cm no melhor caso.
124

Um Sistema de Auxílio à Localização de Etiquetas RFID em Ambientes Internos

SILVA, Rafael de Amorim 31 January 2008 (has links)
Made available in DSpace on 2014-06-12T15:54:13Z (GMT). No. of bitstreams: 2 arquivo1968_1.pdf: 1489303 bytes, checksum: 9151dc2eeb9d80be3a7f67948c9d42e7 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Esta dissertação propõe um sistema de auxílio à localização de etiquetas RFID em ambi- entes internos ou indoor. O sistema é construído sobre o sistema de localização LAND- MARC e fornece duas estimativas da área delimitada na qual se encontra a etiqueta a ser localizada. A primeira estimativa é obtida realizando-se um mapeamento com base em informações providas pelo LANDMARC. A segunda estimativa é obtida realizando-se um mapeamento com base em informações providas por um novo algoritmo também proposto nesta dissertação. A segunda estimativa é utilizada sempre que a informação provida com base na execução do LANDMARC mostra-se errônea. O LANDMARC e o sistema proposto foram avaliados através de simulações com o auxílio do Matlab. As avaliações realizadas consideraram a inconstância típica da força de sinais de rádio-frequência com e sem obstáculos. Os resultados de simulação demonstram que o sistema proposto melhora a eficiência de localização em até 46% com relação à utilização do sistema LANDMARC puro
125

RFID-baserad identifikation i vården

Ström, Patrik January 2015 (has links)
Det här arbetet har syftat till att utvärdera möjligheterna till att använda Raspberry Pi 2, som en del av ett identifikationssystem i vårdmiljöer. Rapporten tar upp och utvärderar möjligheterna att använda olika hårdvara och mjukvara tillsammans med Raspberry Pi, så som olika RFID-läsare, operativsystem och styrmjukvara till RFID-läsarna. Rapporten tar även upp tidigare forskning och implementationer av RFID-användning i vårdmiljöer. Från början var målet att använda Snappy Ubuntu Core som operativsystem, men laborativt arbete visade att Snappy Ubuntu Core inte riktigt hade vad som krävdes för att uppfylla syftet. Arbetet har resulterat i konstruerad mjukvara för att styra och läsa av RFID-kort med en av RFID-läsarna som testats, och det har även experimenteras med Node-RED tillsammans med RFID-mjukvaran.
126

Analyzátor UHF RFID komunikace založený na SDR / SDR-based UHF RFID communication analyzer

Vychodil, Josef January 2013 (has links)
Main topic of this thesis is development of software for capture and analysis of RFID communication in UHF band (standard EPC Class-1 Generation-2). One part of the work is focused on the basics of the RFID systems, software defined radio concept and graphical programming language LabVIEW. Main part of this thesis is discussing the developed software itself, its methods and principles. Next part is dedicated to present the graphical user interface of created application and its functionality. Last part of this thesis contains examples of captured and analysed processes in UHF RFID communication.
127

RFID Tag Design and Range Improvement

Chirammal Ramakrishnan, Rijwal January 2012 (has links)
Radio Frequency Identification (RFID) is a short range radio technology for communication between two objects namely, a reader and a tag. Design of an RFID tag with the best range is always the motive of an RFID designer. In this thesis two RFID tags were simulated, designed and manufactured. The first one is a semi-passive RFID tag, which also serves as a discrete prototype tag for the research group to master RFID tag designs. The user can program and further extend the use of this tag according to the requirements. This RFID tag is provided with JTAG interface to program and debug. The read range of this prototype tag is found to be 1m with reader EIRP of 30dBm. The second design is a passive tag which can be commercialized. It achieves a competitive read range of 2.9m for reader EIRP of 21dBm. The read range when measured in a practical implementation inside a building corridor was 15m.
128

Der Einsatz von Robotern in Bibliotheken: Bestandsaufnahme, Ausblick und Akzeptanz

Nathan, Amy 29 March 2023 (has links)
Roboter sind seit Jahren ein aktuelles Thema und spielen eine immer wichtigere Rolle in vielen Bereichen. Auch in Bibliotheken sind Roboter immer öfter zu finden. Gegenstand dieser Bachelorarbeit soll der Einsatz von Robotern in Bibliotheken sein. Das Ziel dieser Arbeit ist eine möglichst umfassende Bestandsaufnahme der Roboter, die aktuell in Bibliotheken eingesetzt werden. Dafür werden die unterschiedlichen Einsatzmöglichkeiten erläutert und mit Beispielen veranschaulicht. Ferner werden NAO und Pepper vorgestellt, da diese beiden Roboter in Deutschland in Bibliotheken derzeit am häufigsten zum Einsatz kommen. Neben allgemeinen Infos werden die Programmierung und mögliche Probleme der Roboter erläutert. Außerdem wird ein Ausblick auf zukünftige Einsatzmöglichkeiten gegeben und darauf eingegangen, warum diese noch nicht umgesetzt wurden. Im empirischen Teil der Arbeit wird die Einstellung von Bibliotheksnutzern und -mitarbeitern zu dem Thema erfasst und untersucht. Mithilfe einer Umfrage wird die Meinung der Befragten zu Robotern allgemein und zu spezifischen Einsatzmöglichkeiten von Robotern in Bibliotheken ermittelt.:Abkürzungsverzeichnis 1 Einleitung 1.1 Ziel und Fragestellung 1.2 Aufbau der Arbeit 2 Grundlagenkapitel 2.1 Definition des Begriffs „Roboter“ 2.2 Grundlagen von RFID 2.3 Gründe für den Einsatz von Robotern in Bibliotheken 3 Aktuelle Anwendungsfelder 3.1 Erstellung von Inventuren 3.2 Transportroboter 3.3 Scanroboter 3.4 Off-Site-Shelving Roboter 3.5 Programmieren lernen mit Robotern 3.6 Leseförderung mithilfe von Robotern 3.7 Serviceroboter 3.8 Roboter, die Nutzer zu Medien führen 3.9 Telepräsenzroboter 3.10 Mobiler Rückgabeautomat 4 Technische Grundlagen und Herausforderungen am Beispiel von NAO und Pepper 4.1 Vorstellung von NAO und Pepper 4.1.1 NAO 4.1.2 Pepper 4.2 Programmierung der Roboter 4.3 Grenzen der Roboter 5 Zukünftige Anwendungsmöglichkeiten 5.1 Inventurroboter: weitere Möglichkeiten 5.2 Roboter suchen Bücher, nehmen sie aus dem Regal und bringen Sie zu Nutzern 5.3 Roboter, die Bücher einstellen können 5.4 Barrieren überwinden - Gedankenspiel: Wie kann man bereits vorgestellte Technologien nutzen, um Barrierefreiheit voranzutreiben? 6 Akzeptanz von Robotern in Bibliotheken 6.1 Erstellung und Durchführung der Umfrage 6.2 Ergebnisse der Umfrage für Bibliotheksnutzer 6.2.1 Bibliotheksnutzung 6.2.2 Allgemeine Einstellung zu Robotern 6.2.3 Einstellung zu Robotern in Bibliotheken 6.2.4 Wer hat geantwortet? 6.3 Ergebnisse der Umfrage für Bibliotheksmitarbeiter 6.3.1 Allgemeine Einstellung zu Robotern 6.3.2 Einstellung zu Robotern in Bibliotheken 6.3.3 Wer hat geantwortet? 6.4 Auswertung und Vergleich 6.5 Zusammenfassung der Ergebnisse 7 Fazit Abbildungsverzeichnis Tabellenverzeichnis Glossar der erwähnten Roboter Literaturverzeichnis A Anhang A.1 Umfrage für Bibliotheksnutzer A.2 Umfrage für Bibliotheksmitarbeiter A.3 Ergebnisse der Umfrage für Bibliotheksnutzer A.4 Ergebnisse der Umfrage für Bibliotheksmitarbeiter
129

Antenas pequeñas en UHF

Peruzzi, Victor Marcelo 23 June 2021 (has links)
La revolución tecnológica iniciada a mediados del siglo pasado con la invención del transistor, a puesto en nuestras manos un sinnúmero de dispositivos electrónicos que están transformando la sociedad moderna. El teléfono inteligente posiblemente es el más notorio de ellos. Todo indica que en el futuro cercano se incrementaría la cantidad de elementos de uso masivo que harán uso de comunicaciones inalámbricas y en los que la antena será uno de sus componentes fundamentales. Los consumidores presionan para que estos dispositivos sean cada vez más pequeños, tengan menor consumo de energía y puedan transmitir mayores tasas de información, requerimientos que en última instancia se trasladan a sus antenas. En contraposición, sus prestaciones dependen en gran medida de su tamaño en relación a la longitud de onda, y por lo tanto reducir sus dimensiones implica deteriorar su ganancia, e ciencia o ancho de banda. Hay en ellas, como siempre sucede en la ingeniería, un balance entre lo que la aplicación requiere y lo que la física permite. Esta tesis trata sobre estas antenas, denominadas eléctricamente pequeñas y se enfoca en dos aplicaciones: las comunicaciones satelitales y los sistemas UHF RFID; proponiendo soluciones novedosas para mejorar sus prestaciones como así también facilitar su diseño. Se presentarán dos antenas cuyo rasgo distintivo es que irradian ondas con polarización circular y están diseñadas a partir de elementos sencillos, los dipolos acortados. Una de ellas, destinada a un satélite pequeño, aprovecha la propia estructura metálica del satélite para mejorar las prestaciones de los dipolos cruzados. La otra, destinada a un tag de UHF RFID, se distingue por incorporar una red de adaptación de impedancias simple y que permite la fabricación de la antena con costos bajos, requerimiento fundamental de los sistemas de identifi cación automática. Diseñar una antena con estas características requiere conocer a priori la impedancia del chip, para lo cual se ideó un procedimiento que, a diferencia de los métodos convencionales, permite caracterizarla completamente. En tanto que para la antena se desarrolló una técnica de medición basada en un balun de bajo costo construido en placas de circuito impreso. / The technological revolution that began in the middle of the last century with the invention of the transistor put in our hands countless electronic devices that are transforming modern society. The smartphone is possibly the most notorious of them. Everything points to the fact that shortly the number of mass-use items that will make use of wireless communications, and where the antenna will be one of its fundamental components will increase. Consumers are pushing for these devices to become smaller, have lower power consumption, and can transmit higher rates of information, requirements that ultimately transfer to their antennas. In contrast, its performance depends to a large extent on its size relative to the wavelength, and therefore reducing its dimensions involves impairing its gain, e ciency, or bandwidth. There is in them, as always happens in engineering, a balance between what the application requires and what physics allows. This thesis deals with these antennas, called electrically small and focuses on two applications: satellite communications and UHF RFID systems; proposing novel solutions to improve its performance as well as facilitate its design. Two antennas will be presented, whose distinctive feature is that they radiate waves with circular polarization and are designed from simple elements, the shortened dipoles. One of them, intended for a small satellite, takes advantage of the satellite's metal structure to improve the performance of the crossed dipoles. The other, intended for an RFID UHF tag, is distinguished by incorporating a simple impedance matching network, and which allows the manufacture of the antenna with low costs, a fundamental requirement of automatic identi cation systems. Designing an antenna with these characteristics requires a priori knowledge of the chip impedance, for which a procedure was designed that, unlike conventional methods, allows it to be fully characterized. While for the antenna, a measurement technique was developed based on a low-cost balun built on printed circuit boards.
130

Analysis of an Embedded Singularity Chipless RFID Tag

Blischak, Andrew Travis 28 July 2011 (has links)
The objective of this research is to explore the feasibility of a chipless RFID tag that stores a data signature in the form of complex frequency plane singularities. To this end an existing chipless RFID tag, the notched elliptical dipole tag, was analyzed first with simulations and then measurements. A pole signature was extracted from simulations, and individual poles were determined via experimentation to be attributable to specific controllable features of the tag. The poles were shown to be independent of both excitation and observation. A prototype tag was measured, and the pole signature was retrieved from the scattered fields. The tag was successfully read for different orientations showing that embedded singularities can be used as a means for encoding and retrieving data. / Master of Science

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