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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.
161

Real-time Location with ZigBee Hardware

Franzese, Anthony L. 20 April 2011 (has links)
No description available.
162

DESIGN AND DEVELOPMENT OF A FALL DETECTION DEVICE WITH INFRARED RECEIVING CAPABILITIES

Ramzi, Ammari 24 August 2011 (has links)
No description available.
163

Hybrid FPGA and GPP Implementation of IEEE 802.15.4 Physical Layer

Jeong, Jeong-O 28 August 2012 (has links)
In this thesis, two different cases of hybrid IEEE 802.15.4 PHY (Physical Layer) implementation are explored. The first case is an FPGA implementation of IEEE 802.15.4 PHY on the Xilinx Spartan-3A DSP FPGA of USRP N210. All of the signal processing tasks are performed on the FPGA, while less complex MAC (Media Access Control) layer tasks are performed in GNU Radio on the host. The second case is an implementation of a multi-channel IEEE 802.15.4 receiver. A four-channel channelizer is implemented on the external Virtex 5 FPGA, while the IEEE 802.15.4 receiver is implemented in GNU Radio on the host. The first case demonstrates how spare resources in USRP's FPGA can be used to implement signal processing task while still interfacing with GNU Radio. The second case builds a platform on which a combination of GNU Radio and an external FPGA can be used for signal processing and USRP as an RF source. This thesis lays out the groundwork for more complex wireless protocols to be implemented on any combination of USRP's FPGA, an external FPGA, and GNU Radio. / Master of Science
164

Evaluation of GNU Radio Platform Enhanced for Hardware Accelerated Radio Design

Karve, Mrudula Prabhakar 05 January 2011 (has links)
The advent of software radio technology has enabled radio developers to design and implement radios with great ease and flexibility. Software radios are effective in experimentation and development of radio designs. However, they have limitations when it comes to high-speed, high-throughput designs. This limitation can be overcome by introducing a hardware element to the software radio platform. Enhancing GNU Radio for Hardware Accelerated Radio Design project implements such a scheme by augmenting an FPGA co-processor to a conventional GNU Radio flow. In this thesis, this novel platform is evaluated in terms of performance of a radio design, as well as hardware and software system requirements. A simple and efficient Zigbee receiver design is presented. Implementation of this receiver is used as a proof-of-concept for the effectiveness and design methodology of the modified GNU Radio. This work also proposes a scheme to extend this idea for design of ultra-wideband radio systems based on multiband-OFDM. / Master of Science
165

Análise de arquiteturas e desenvolvimento de uma plataforma para residências inteligentes. / Architecture analysis and development of framework for intelligent houses.

Bolzani, Caio Augustus Morais 18 December 2009 (has links)
No início do século XX, poucas décadas depois do início da eletrificação das casas, o conceito de uma residência automatizada já era utilizado como símbolo de um futuro livre das tarefas domésticas. No entanto, mesmo com o desenvolvimento de tecnologias de suporte, a automação de residências nunca contemplou uma ampla disseminação e uso. Este trabalho realiza uma análise social, econômica, tecnológica, cultural e de saúde da sociedade, desde o início do século XX até os dias atuais, para entender o comportamento humano relativo ao ambiente residencial e identificar as possíveis causas que não favoreceram a implantação de sistemas de controle e automação nestes ambientes. Ele ainda propõe uma arquitetura de sistemas eletrônicos e computacionais para o ambiente residencial, baseada em um conjunto de requerimentos e de abstrações coerentes com o contexto socioeconômico vigente e factível diante das atuais disponibilidades tecnológicas, a fim de direcionar os esforços na área e fomentar o desenvolvimento de aplicações. Adicionalmente, é apresentada uma plataforma de desenvolvimento hardware, firmware e software , denominada Home Sapiens, cuja concepção, projeto e desenvolvimento foram feitos no contexto desta tese. Baseada em nós de controle distribuídos, ela permite o acesso aos dados provenientes de sensores, a geração de informações de contexto, a identificação de serviços e a manipulação das características do ambiente residencial segundo regras de decisão, planejamento e métodos de aprendizado baseados em técnicas de Inteligência Artificial / In the early twentieth century, a few decades after the beginning of the electrification of houses, the concept of an automated home was used as a symbol of a future free of domestic chores. However, even with the development of supporting technologies, the automation of homes never contemplated a wide dissemination and use. This paper presents an analysis social, economic, technological, cultural and health of society, from the early twentieth century to the present day, to understand human behavior on the residential environment and to identify possible causes that did not favor deployment of control systems and automation in these environments. It also proposes an architecture of computer and electronic systems for the residential environment, based on a set of applications and abstractions consistent with the current socioeconomic context and feasible under the available technology in order to direct efforts in the area and promote the development of applications. Additionally, the implementation of a framework hardware, firmware and software called Home Sapiens is presented, whose conception, design and development were made in the context of this thesis. Based on distributed control nodes, it provides access to data from sensors, the generation of information of context, the identification of services and handling characteristics of the residential environment in accordance with rules of decision, planning and learning methods based on Artificial Intelligence.
166

Análise de arquiteturas e desenvolvimento de uma plataforma para residências inteligentes. / Architecture analysis and development of framework for intelligent houses.

Caio Augustus Morais Bolzani 18 December 2009 (has links)
No início do século XX, poucas décadas depois do início da eletrificação das casas, o conceito de uma residência automatizada já era utilizado como símbolo de um futuro livre das tarefas domésticas. No entanto, mesmo com o desenvolvimento de tecnologias de suporte, a automação de residências nunca contemplou uma ampla disseminação e uso. Este trabalho realiza uma análise social, econômica, tecnológica, cultural e de saúde da sociedade, desde o início do século XX até os dias atuais, para entender o comportamento humano relativo ao ambiente residencial e identificar as possíveis causas que não favoreceram a implantação de sistemas de controle e automação nestes ambientes. Ele ainda propõe uma arquitetura de sistemas eletrônicos e computacionais para o ambiente residencial, baseada em um conjunto de requerimentos e de abstrações coerentes com o contexto socioeconômico vigente e factível diante das atuais disponibilidades tecnológicas, a fim de direcionar os esforços na área e fomentar o desenvolvimento de aplicações. Adicionalmente, é apresentada uma plataforma de desenvolvimento hardware, firmware e software , denominada Home Sapiens, cuja concepção, projeto e desenvolvimento foram feitos no contexto desta tese. Baseada em nós de controle distribuídos, ela permite o acesso aos dados provenientes de sensores, a geração de informações de contexto, a identificação de serviços e a manipulação das características do ambiente residencial segundo regras de decisão, planejamento e métodos de aprendizado baseados em técnicas de Inteligência Artificial / In the early twentieth century, a few decades after the beginning of the electrification of houses, the concept of an automated home was used as a symbol of a future free of domestic chores. However, even with the development of supporting technologies, the automation of homes never contemplated a wide dissemination and use. This paper presents an analysis social, economic, technological, cultural and health of society, from the early twentieth century to the present day, to understand human behavior on the residential environment and to identify possible causes that did not favor deployment of control systems and automation in these environments. It also proposes an architecture of computer and electronic systems for the residential environment, based on a set of applications and abstractions consistent with the current socioeconomic context and feasible under the available technology in order to direct efforts in the area and promote the development of applications. Additionally, the implementation of a framework hardware, firmware and software called Home Sapiens is presented, whose conception, design and development were made in the context of this thesis. Based on distributed control nodes, it provides access to data from sensors, the generation of information of context, the identification of services and handling characteristics of the residential environment in accordance with rules of decision, planning and learning methods based on Artificial Intelligence.
167

Étude et développement d'une plateforme de communication pour les réseaux de capteurs acoustiques sans fil : application au contrôle-santé des rails par corrélation du bruit ambiant / Study and development of a communication platform for wireless acoustic sensor networks : application to health monitoring of rails using ambient noise correlation

Sadoudi, Laïd 06 July 2016 (has links)
Le Contrôle-Santé Intégré (CSI) réduit les besoins d’inspections humaines grâce à une surveillance automatisée, réduit les coûts de maintenance grâce à la détection précoce des anomalies avant qu’elles ne dégénèrent et améliore la sécurité ainsi que la fiabilité des services. L’objectif de cette thèse est de concevoir une plateforme de communication sans fil pour le CSI des structures ferroviaires. Le principe de contrôle repose sur la reconstruction des réponses impulsionnelles (fonctions de Green) par corrélation de bruit aléatoire se propageant dans le milieu. Durant ces travaux, nous avons éprouvé expérimentalement la relation entre les réponses actives expérimentales et une version post-traitée des fonctions de corrélation de bruit dans un contexte ferroviaire. Ainsi, nous avons démontré l’applicabilité des fonctions de corrélation pour la détection d’un défaut local sur un rail. Ensuite, nous avons réalisé une étude expérimentale comparative sur la caractérisation d’une transmission ZigBee en termes d’atténuation et de portée dans plusieurs environnements. Dans l’environnement ferroviaire sous test, nous avons démontré l’adéquation avec la portée d’une transmission ZigBee mono-saut (dans un rayon de 76m). Une solution de synchronisation des capteurs lors du prélèvement du signal basée sur la norme IEEE 802.15.4 a été proposée et validée par une campagne de mesures. Il a été démontré que cette approche offre une précision de l’ordre de quelques centaines de nanosecondes. Un prototype-plateforme de communication sans fil basé sur la technologie ZigBee/IEEE 802.15.4 a été mis en place et déployé sur un échantillon de rail. Cette solution a permis de valider les performances de cette plateforme, une fois les données récoltées par les transducteurs, ces informations sont transmises par un lien ZigBee vers une station de base où des algorithmes de détection leurs sont appliqués. / Structural Health Monitoring (SHM) reduces human inspection requirements through automated monitoring, reduces maintenance costs by early detection of defects before they escalate, and improves safety and reliability of services. The work presented in this thesis aims to design a wireless communication platform for railway structures health monitoring. The control principle is based on the reconstruction of impulse responses (Green’s functions) by correlation of random noise propagated in the medium. In this work, direct comparison between an active emission-reception response and the estimated noise correlation function has confirmed the validity of the equivalence relation between them. Thus, we have demonstrated the applicability of the correlation functions for local defect detection in a rail. Then, we conducted an experimental study on the characterization of a ZigBee transmission in terms of path loss and communication range in multiple environments. In the railway environment under test, we showed the adequacy with the range of a ZigBee single-hop transmission (within a radius of 76m). Furthermore, a flexible solution for sensors synchronization during the sampling process, based on IEEE 802.15.4 standard was proposed and validated by a measurement campaign. It has been demonstrated that this approach provides a precision of a few hundred nanoseconds. A wireless communication-platform prototype based on the ZigBee/IEEE 802.15.4 technology has been implemented and deployed on a rail sample. This solution enabled the validation of the platform performances, once the data collected by the transducers, the information is transmitted by a ZigBee link to a base station where detection algorithms are applied.
168

Étude et mise en oeuvre d'une plateforme hybride basée sur du sans fil pour l'efficience énergétique et le contrôle d'accès dans le train / Study and implementation of hybrid platform based on wireless network for energy efficiency and access control in the train

Biaou, Ulrich 11 December 2017 (has links)
Les besoins de nouveaux services dans les rames ferroviaires ( le comptage, l’efficience énergétique, le confort et la sécurité des passagers etc.), risquent de saturer à terme les systèmes de communication filaires mis en place il y a une vingtaine d’années. Les réseaux de capteurs sans fil, par leurs avantages (déploiement facile, capacité à s’adapter à plusieurs types d’environnements, faible consommation d’énergie), ouvrent de nombreuses perspectives pour les systèmes de gestion énergétique. Le but de ce travail de thèse est d’étudier et mettre en oeuvre un réseau de capteurs sans fil à l’intérieur des trains pour l’efficience énergétique. Ainsi, quelques protocoles de communication dédiés à la gestion énergétique ont été présentés puis une étude comparative des différents réseaux de communication sans fil réalisée. Cette étude comparative a permis de faire le choix du réseau ZigBee comme étant le plus adéquat pour la plateforme. L’architecture hybride proposée permet l’utilisation du réseau IP existant comme colonne vertébrale de l’ensemble des réseaux ZigBee. Afin de tenir compte de l’effet de l’environnement ferroviaire dans la planification et le déploiement du réseau, une étude du canal de propagation, basée sur des mesures réalisées dans un métro et un wagon de RER a été menée. L’impact de la coexistence entre le ZigBee et le WiFi et de la présence humaine sur la communication du réseau sans fil a été démontré. Le prototype d’une plateforme basée sur le réseau ZigBee allant de la collecte des données à l’affichage des informations a été réalisé et testé. / The need of new services in railway trains (services for metering, energy efficiency, the comfort and safety of users etc.) may eventually saturate the wired communication systems installed since twenty years ago years. The several advantages of wireless sensor networks (easy deployment, ability to adapt on different environments and low energy consumption) offer many possibilities for energy management systems. The aim of this thesis is to study and implement a wireless network sensors inside trains for energy efficiency. Thus, some communication protocols dedicated to energy management were presented and then a comparative study of the various wireless communication networks carried out. This comparative study shows that the ZigBee network is the most suitable for the platform. The proposed hybrid architecture allows the use of the existing IP network as the backbone of all ZigBee networks. In order to take into account the effect of the railway environment in the planning and deployment of the network, a study of the propagation channel was carried out, based on measurements realized in a subway and a RER car. The impact of the coexistence between ZigBee and WiFi and of the human presence on wireless communication have been demonstrated. The prototype of a platform based on the ZigBee network, allows data collection, informations traitement and monitoring, was carried out.
169

Monitoramento, controle e parametrização de eletrodomésticos numa rede sem fio via interface virtual remota

Watanabe, Ana Teruko Yokomizo 29 May 2008 (has links)
Made available in DSpace on 2016-12-12T17:38:35Z (GMT). No. of bitstreams: 1 Ana Teruko.pdf: 11607034 bytes, checksum: 72b3906b42ad639d1abd56a8054d9ffe (MD5) Previous issue date: 2008-05-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The wireless communication in the residential automation has became a very promising technology due to the easinesses in the installation, and for its flexibility, mobility and scalability. Inside this context, the objective of this work is to analyze and to implement two wireless communication standard protocols: Bluetooth and ZigBee. They are used to analyze theirs functionalities and applications under a domestic environment. Firstly, the Bluetooth protocol was used in order to verify its operation because this one is an already well known protocol. Secondly, the ZigBee protocol - IEEE 802.15.4 MAC was also tested due to its new protocol applied to small data communication and its low baud rate, star topozlogy and low energy consumption, which allows the control of householdelectric network. The project consisted of monitoring, controlling and configuring washing machines by using a wireless network through a remote virtual interface. The user interface of this system was done through a PDA (Personal Digital Assistant), which allowed to change the times of washing programs manual or automatic mode. The results indicated the feasibility of monitoring and controlling household-electric by implementing the IEEE 802.15.4 MAC Layer of ZigBee protocol. This implementing reached the main characteristics as described above. The maximum distance achieved in a star topology in the typical residence was 14 meters, without using routers. This distance can be increased implementing full ZigBee Protocol. Although the project was developed to washing machine, it also can be implemented to other household-electrics, such as: microwaves, heaters, air conditioners, refrigerators, etc. / A comunicação sem fio em automação residencial tem se tornado uma tecnologia muito promissora devido às facilidades na instalação, flexibilidade, mobilidade e escalabilidade. Dentro deste contexto, o objetivo deste trabalho é analisar e implementar dois padrões de comunicação sem fio: Bluetooth e ZigBee, a fim de analisar suas funcionalidades e aplicações em ambiente doméstico. O protocolo Bluetooth por se tratar de um protocolo já consagrado no mercado, foi utilizado no controle remoto de uma máquina lavadora, como proposta inicial deste trabalho. Depois, o protocolo ZigBee - IEEE 802.15.4 MAC foi implementado, pois este padrão é um protocolo novo aplicado a comunicação com pequenos pacotes de dados, baixa taxa de transmissão, topologia estrela e baixo consumo de energia, que são características importantes para controle de uma rede de eletrodomésticos. O projeto consistiu em desenvolver um protótipo de hardware e de software para monitorar, controlar e parametrizar máquinas lavadoras de roupas numa rede sem fio através de uma interface virtual remota. Esta interface do usuário com a rede foi feita através de um PDA (Personal Digital Assistant) que permitiu alterar os tempos de programação da máquina no modo manual ou automático. Os resultados mostraram a viabilidade de se construir uma rede de eletrodomésticos, implementando a camada de enlace IEEE 802.15.4MAC do protocolo de comunicação ZigBee. Esta implementação atingiu as principais características descritas acima. A distância máxima alcançada na topologia estrela numa residência típica foi de 14 metros, sem o uso de roteadores. Esta distância poderá ser aumentada através da implementação da camada de rede ZigBee. Embora o projeto tenha sido desenvolvido utilizando máquinas lavadoras, pode-se estendêlo a outros eletrodomésticos tais como: fornos de microondas, aquecedores, condicionadores de ar, refrigeradores, etc.
170

InteliCare Infraestrutura de Telessaúde para apoio a serviços de atenção domiciliar baseada em redes de sensores sem fio e sistemas embarcados

Morais, Bruno Maia de 20 August 2012 (has links)
Made available in DSpace on 2015-05-14T12:36:41Z (GMT). No. of bitstreams: 1 arquiuvototal.pdf: 6365528 bytes, checksum: 4e27c7390c2e3c53b8c85b58dabd1b55 (MD5) Previous issue date: 2012-08-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work presents a monitoring infrastructure for people in a situation of home care through the integration of wireless sensor networks and data processing in embedded systems, enabling a real-time monitoring of the clinical picture of each patient. To perform real-time telemetry, a sensor network with ZigBee technology was set and some biological signals were captured in order to validate the proposed infrastructure. This network performs the capture and transmission of data collected to base stations where a treatment system embedded in an FPGA is instructed to receive data, perform the necessary calculations and send the information obtained through an Ethernet network to a central installed in a monitoring central station. The use of a dedicated processing device such as an FPGA, provides a much greater efficiency than is typically found in general purpose processors and allows the customization of the hardware. Besides, reduces the final cost of the system. It also presented the integration of Arthron and InteliCare. Arthron is tool that works with flow distribution. This integration allows more real experiences of telemedical procedures so that you can have in a single transmission, audio, video, and biological signals. The monitoring system installed in the central station is responsible for storage and display the received data. It will display data in tables and graphs in real time and allow a team of experts make decisions and guide patients and / or their caregivers to perform a certain procedure. / Este trabalho apresenta uma infraestrutura de monitoramento para pessoas em situação de internação domiciliar através da integração de redes de sensores sem fio e processamento de dados em sistemas embarcados, possibilitando um acompanhamento em tempo de execução (online) do quadro clínico de cada paciente. Para realizar a telemetria online, uma rede de sensores com tecnologia ZigBee, foi montada e alguns sinais biológicos foram captados de forma a validar a infraestrutura proposta. Esta rede realiza a captação e envio dos dados coletados até estações base onde um sistema de tratamento embarcado em um FPGA fica encarregado de receber os dados, realizar os cálculos necessários e enviar as informações obtidas, através de uma rede Ethernet, a um sistema central de supervisão instalado em uma central de monitoramento. A utilização de um dispositivo de processamento dedicado, como um FPGA, proporciona ao sistema uma eficiência muito maior do que normalmente é encontrada em processadores de uso geral além de permitir a customização do hardware reduzindo o custo final do sistema. É apresentada também a integração da infraestrutura InteliCare com a ferramenta de distribuição de fluxos Arthron. Esta integração permite tornar mais real a experiência de colaboração em procedimentos médicos de forma que é possível ter numa mesma transmissão, áudio, vídeo e sinais biológicos. O sistema de supervisão instalado na central de monitoramento é responsável por gerenciar o armazenamento e a visualização dos dados recebidos. Ele exibe os dados em tabelas e gráficos em tempo de execução e permitirá que uma equipe de especialistas tome decisões e oriente os pacientes e/ou seus cuidadores para realizar determinado procedimento.

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