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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.
221

The Design, Building, and Testing of a Constant on Discreet Jammer for the IEEE 802.15.4/ZIGBEE Wireless Communication Protocol

Marette, Alexandre J 01 June 2018 (has links) (PDF)
As wireless protocols become easier to implement, more products come with wireless connectivity. This latest push for wireless connectivity has left a gap in the development of the security and the reliability of some protocols. These wireless protocols can be used in the growing field of IoT where wireless sensors are used to share information throughout a network. IoT is being implemented in homes, agriculture, manufactory, and in the medical field. Disrupting a wireless device from proper communication could potentially result in production loss, security issues, and bodily harm. The 802.15.4/ZigBee protocol is used in low power, low data rate, and low cost wireless applications such as medical devices and home automation devices. This protocol uses CSMA-CA (Carrier Sense Multiple Access w/ Collision Avoidance) which allows for multiple ZigBee devices to transmit simultaneousness and allows for wireless coexistence with the existing protocols at the same frequency band. The CSMA-CA MAC layer seems to introduce an unintentional gap in the reliability of the protocol. By creating a 16-tone signal with center frequencies located in the center of the multiple access channels, all channels will appear to be in use and the ZigBee device will be unable to transmit data. The jamming device will be created using the following hardware implementation. An FPGA connected to a high-speed Digital to Analog Converter will be used to create a digital signal synthesizer device that will create the 16-tone signal. The 16-tone signal will then be mixed up to the 2.4 GHz band, amplified, and radiated using a 2.4 GHz up-converter device. The transmitted jamming signal will cause the ZigBee MAC layer to wait indefinitely for the channel to clear. Since the channel will not clear, the MAC layer will not allow any transmission and the ZigBee devices will not communicate.
222

Scheduling and Simulation of Large Scale Wireless Personal Area Networks

Wang, Qihe 21 July 2006 (has links)
No description available.
223

Laborationer med trådlösa sensornät

Degirmenci, Cecilia, Alsakban, Hamed January 2009 (has links)
Trådlösa sensornät (eng. Wireless Sensor Networks, WSN) är ett snabbt växande teknikområde med många applikationer. Ett typiskt WSN består av en mängd små billiga och energisnåla enheter, så kallade sensornoder, som mäter någon miljöparameter och via radio skickar ett datapaket med uppmätt värde till en basstation som ofta är kopplad till en PC. Informationen kan därefter analyseras eller redovisas grafiskt för användaren. Sensornätverkets storlek kan variera från några få noder på en liten yta till nätverk med tusentals noder som täcker flera kvadratkilometer stora områden. Ett avsnitt om trådlösa sensornät ingår i kursen Data- och telekommunikationsteknik II, DA122T, vid Malmö högskola. Denna rapport presenterar ett examensarbete med att utveckla laborationer och studiematerial om sensornät till kursen.Utrustningen som används i laborationerna är ett paket innehållande sex sensornoder, en basstation och nödvändig programvara. Tillverkare är Crossbow Technology, världens ledande företag inom WSN.Resultatet av arbetet är två laborationshandledningar, beskrivning av utrustning som används i laborationerna samt en rapport – Introduktion till WSN. Handledningarna och det övriga materialet är skrivna på svenska.Den första laborationen, i vilken man bygger ett enkelt WSN, ger studenten förståelse för principen hos trådlösa sensornät och för hur hårdvaran och programvaran samverkar med varandra. I den andra laborationen lär sig studenten programmera sensornoder för att sedan studera kommunikationen mellan noderna och basstationen samt undersöka olika nätverkstopologier. / Wireless sensor networks, WSN, is a rapidly growing field of technology with many applications. A typical WSN consists of many small, inexpensive and energy-saving devices, called sensor nodes. These nodes measure an environmental parameter and the radio sends a data packet with the measured value to a base station, which is often connected to a PC. The information can then be analyzed and presented graphically to the user. A sensor network's size can vary from a few nodes in a small area to a network with thousands of nodes that covers several square kilometers of area. A section on wireless sensor networks is part of the course in Computer and telecommunication technologies II, DA122T, at Malmö University. This thesis reports on the development of study material for the practical laboratory motes on sensor networks for the course. The equipment used in the practical experiments is a package containing six sensor nodes, a base station and the necessary software. The manufacturers are Crossbow Technology, the world's leading company of WSN products. The results of the work are two practical exercises, a description of the equipment used in practical experiments and a report – Introduction to WSN. These guides and other materials are written in Swedish. The first lab in which to build a simple WSN, gives students an understanding of the principle of wireless sensor networks and how the hardware and software interacts with each other. In the second exercise, students will learn to program the sensor nodes to study the communication between the nodes and the base station and to explore the different network topologies.
224

Estudo e especifica??o de um sistema de instrumenta??o para unidades de eleva??o de petr?leo utilizando tecnologia sem fio

Campos, Carlo Frederico Pereira de Siqueira 27 November 2006 (has links)
Made available in DSpace on 2014-12-17T14:56:21Z (GMT). No. of bitstreams: 1 CarloFPSC.pdf: 941846 bytes, checksum: 5fe2e2c9851039018a0653de693d001c (MD5) Previous issue date: 2006-11-27 / Wireless sensor networks are reality nowadays. The growing necessity of connectivity between existing industrial plant equipments pushes the research and development of several technologies. The IEEE 802.15.4 LR-WPAN comes as a low-cost and powersaving viable solution, which are important concerns while making decisions on remote sensoring projects. This study intends to propose a wireless communication system which makes possible the monitoring of analogic and/or digital variables (i. e., the pressure studied) involved on the artificial methods for oil and gas lifting. The main issues are: To develop a software based on SMAC Standard in order to create a wireless network to monitoring analogic and/or digital variables; To evaluate the communication link based on the number of lost packets tested in different environments (indoor and outdoor) and To propose an instrumentation system consisting of wireless devices / As redes de sensores sem fio (RSSS) j? s?o uma realidade hoje em dia, pois a grande necessidade de conectividade entre os equipamentos existentes numa planta industrial impulsiona a pesquisa e o desenvolvimento de diversas tecnologias. O padr?o LR-WPAN IEE 802.15.4 apresenta-se como uma solu??o vi?vel, com baixo custo e baixo consumo de energia, requisitos importantes para a implanta??o de um sistema de sensoriamento remoto. A contribui??o deste trabalho consiste em propor um sistema de comunica??o sem fio, que possa monitorar vari?veis anal?gicas e/ou digitais (no caso do estudo em quest?o, a press?o) nos m?todos de eleva??o artificial de petr?leo e g?s natural. Os pontos principais deste estudo s?o: Desenvolver um software baseado no Padr?o SMAC com intuito de criar uma rede sem fio com fins de monitoramento de vari?veis anal?gicas e/ou digitais; Avaliar o enlace de comunica??o com rela??o a quantidade de pacotes perdidos em diferentes ambientes (ambientes internos (Indoor) e externos (Outdoor)) e, Propor um sistema de instrumenta??o utilizando tecnologia sem fio
225

Korsplattformskommunikation med Bluetooth Low Energy / Crossplatformcommunication with Bluetooth Low Energy

Lindberg, Johan January 2014 (has links)
This project investigated the current market regarding wireless net and the communication between the tools used for diagnostics/maintenance and an embedded system. Based on documentation obtained through interviews a demo system was created based on Bluetooth Low Energy (BLE) communication between an embedded system and an Android device. This report intends to describe the tools and methods used in the design of the demo system and the result of an analysis of the BLE communication. Bluetooth Low Energy is an exciting protocol with wide applicability within the industrial field. This project investigated the communicational possibilities between a Smartphone and a Raspberry Pi and based on the results that emerged the conclusion can be drawn that BLE is a protocol with many beneficial applications within industrial IT. / Projektet undersökte dagens marknad gällande trådlösa nät samt kommunikation mellan verktyg som används för diagnostik/underhåll och ett inbyggt system. Utifrån underlaget som erhölls genom intervjuer har ett demosystem skapats som bygger på Bluetooth Low Energy (BLE) kommunikation mellan ett inbyggt system och en Android-enhet. Denna rapport avser redogöra för de verktyg och metoder som använts för att konstruera ett demosystem samt resultatet av en analys av BLE-kommunikationen. Bluetooth Low Energy är ett spännande protokoll med stora tillämpningsmöjligheter inom industrin. Detta projekt har undersökt möjligheterna att kommunicera mellan en Smartphone och en Raspberry Pi och utifrån resultaten som uppkommit kan slutsatsen dras att BLE är ett protokoll som kan ha många och fördelaktiga tillämpningar inom Industriell IT.
226

Vliv přenosových parametrů na spotřebu elektrické energie Zigbee zařízení / Impact of Communication Parameters on Energy Consumption of Zigbee Devices

Popelka, Jan January 2013 (has links)
This thesis deals with the energy research and design a simple wireless sensor networks. The data modules with ZigBee wireless communication technology. The main feature of wireless sensor networks is the minimal energy devices at low cost and maximum data reliability. Furthermore, the work describes firmware for communicating nodes with the ability to change parameters of data transmission and thus affect the energy consumption node. Calculations of energy consumption, compared with measured results and discharge characteristics of the battery packs are included in the final chapters of this work.
227

Vliv přenosových parametrů na spotřebu elektrické energie Zigbee zařízení / Impact of Communication Parameters on Energy Consumption of Zigbee Devices

Popelka, Jan January 2013 (has links)
This thesis deals with the energy research and design a simple wireless sensor networks. The data modules with ZigBee wireless communication technology. The main feature of wireless sensor networks is the minimal energy devices at low cost and maximum data reliability. Furthermore, the work describes firmware for communicating nodes with the ability to change parameters of data transmission and thus affect the energy consumption node. Calculations of energy consumption, compared with the measured results, the discharge characteristics of the battery packs and lifetime broadcasting node is contained in the final chapters of this work.
228

Wireless body-to-body sensor networks : optimization models and algorithms / Réseaux de capteurs corporels sans fils : modèles d'optimisation et algorithmes

Meharouech Ali, Amira 16 December 2016 (has links)
Motivés par la demande croissante de services de santé améliorés et à distance, qui tend à augmenter notamment avec une population de plus en plus âgée, et la réduction du coût de l'utilisation des infrastructures réseaux, afin d'assurer des applications de santé temps-réel et à faible débit de données, les réseaux de capteurs médicaux sans fil (WBANs) forment encore un domaine de recherche en forte croissance, notamment avec le développement de WBANs coopératifs. Dans ce contexte, en utilisant les utilisateurs du réseau eux-mêmes en tant que relais on pourrait étendre les infrastructures réseaux existantes, tout en améliorant la capacité du réseau et optimisant l'utilisation du spectre radio. Ainsi, les opérateurs réseaux, qui planifient déjà pour l'intégration de l'internet des objets (IoT) et l'informatique en nuage (cloud), devraient aussi penser à créer un nouveau type de réseau ad hoc mobile, où les utilisateurs du réseau sont utilisés comme des stations de base ad hoc simplifiées, afin de partager l'information en temps-réel entre des personnes colocalisées portant des capteurs corporels. Ce nouveau type de réseau est appelé réseau corporel sans fil (BBN: Body-to-Body Network). Dans un BBN, un appareil radio, collecte les données des nœuds capteurs attachés ou portés par une personne, et les transmet à un appareil récepteur situé sur une autre personne du voisinage, afin d'être traitées ou retransmises à d'autres utilisateurs du BBN. le BBN peut trouver des applications dans divers domaines tels que la santé, les sports d'équipe, le militaire, les divertissements, ainsi que des expériences passionnantes des réseaux sociaux. Fonctionnant dans la bande Industrielle, Scientifique et Médicale (ISM), les liaisons de communication dans un BBN seront très sensibles aux interférences entre les différentes technologies qui partagent le spectre radio limité. Ainsi, l'interférence entre ces technologies devient une préoccupation importante pour la conception de protocoles pour l'utilisateur final du BBN. À ce jour, très peu d'études existent, qui effectuent une analyse en profondeur de ce type de scénario implicant le corps humain dans des communications radio. Le problème d'interférence dans un tel système distribué, doit être abordé avec des mécanismes distribués, tels que la théorie des jeux. Les décideurs dans le jeu sont soit les WBANs formant le BBN ou les opérateurs de réseaux qui contrôlent les dispositifs de communication inter-WBAN. Ces dispositifs doivent faire face à des ressources de transmission limitées (bande ISM) ce qui donne lieu à des conflits d'intérêts. Cette thèse vise à explorer les opportunités pour permettre des communications inter-WBANs en assurant le partage du spectre radio par le biais de deux approches. D'abord, l'atténuation des interférences mutuelles et croisées, et par la conception d'un protocole de routage spécifique BBN utilisé dans une application de contrôle de l'expansion d'une épidémie dans les zones de rassemblement de masse, tels que les aéroports. Dans un premier volet, une approche basée sur la théorie des jeux est proposée pour résoudre le problème d'interférence distribué dans les BBNs. Le jeu d'atténuation des interférences socialement conscient des intérêts de la collectivité (SIM) a une double tâche: à l'échelle WBAN, il alloue des canaux ZigBee aux capteurs corporels pour la collecte intra-WBAN des données, et à l'échelle BBN, il alloue les canaux WiFi aux appareils mobiles pour la transmission et le relais des données inter-WBANs. Deux algorithmes, BR-SIM et SORT-SIM, ont été développés pour rechercher les points d'équilibre de Nash du jeu SIM. Le premier (BR-SIM) assure les solutions de meilleure réponse (Best-response) tandis que le second (SORT-SIM) tente d'obtenir un compromis entre des solutions quasi-optimales et un temps de convergence réduit. (...) / Motivated by the rising demand for remote and improved healthcare, while decreasing the cost of using network infrastructures to ensure time and data rate-constrained applications, Wireless Body Area Networks (WBANs) still form a strongly growing research field. Besides, engineers and researchers are investigating new solutions to supplement mobile communications through developing opportunities for cooperative WBANs. In this context, using network users themselves as relays could complement and extend existing infrastructure networks, while improving network capacity and promoting radio spectrum usage. Yet, network operators, that are already planning for the Internet of Things (IoT) and cloud computing technologies integration, should also think about this new possibility of creating a new type of mobile ad hoc network, where network users themselves are used as simplified ad hoc base stations, to fulfill the desire of sharing real-time information between colocated persons carrying body sensors. This emerging type of network is called Body-to-Body Network (BBN). In a BBN, a radio device situated on one person gathers the sensor data from the sensor nodes worn by that person, and transmit them to a transceiver situated on another person in the nearby area, in order to be processed or relayed to other BBN users. BBNs can find applications in a range of areas such as healthcare, team sports, military, entertainment, as well as exciting social networking experiences. Operating in the popular Industrial, Scientific and Medical (ISM) band, the communication links in a BBN will be heavily susceptible to interference between the different radio technologies sharing the limited radio spectrum. Thus, inter-body interference become an important concern for protocol design and quality of service for the BBN end user. Yet, higher layer MAC and networking mechanisms need to be in place to overcome this interference problem. To date, very few studies, that perform in-depth analysis of this type of body-centric scenario, exist. The interference problem in such distributed system, should be tackeled with distributed mechanisms, such as Game Theory. The decision makers in the game are either the WBANs/people forming the BBN or the network operators who control the inter-WBAN communicating devices. These devices have to cope with a limited transmission resource (ISM band) that gives rise to a conflict of interests. This thesis aims at exploring the opportunities to enable inter-WBAN communications by ensuring feasible sharing of the radio spectrum through two challenging research issues. First, mutual and cross-technology interference mitigation, and second, the design of a BBN specific routing protocol applied to an epidemic control application within mass gathering areas, such as the airport, as use case in this thesis. In a first phase, a game theoretical approach is proposed to resolve the distributed interference problem in BBNs. The Socially-aware Interference Mitigation (SIM) game performs twofold: at the WBAN stage, it allocates ZigBee channels to body sensors for intra-WBAN data sensing, and at the BBN stage, it allocates WiFi channels to mobile devices for inter-WBAN data transmitting and relaying. Two algorithms, BR-SIM and SORT-SIM, were developed to search for Nash equilibra to the SIM game. The first (BR-SIM) ensures best response solutions while the second (SORT-SIM) attempts to achieve tradeoff between sub-optimal solutions and short convergence time. Then, in order to highlight the social role of BBNs, the second part of this thesis is devoted to propose an epidemic control application tailored to BBNs, in indoor environment. This application implements a geographic routing protocol, that differentiates WBANs traffic and ensures real-time quarantine strategies. (...)
229

Projeto e implementação de um nodo sensor para aquisição de sinais de extensômetros em redes de sensores sem fio aplicado ao monitoramento de deformações em estruturas

ATAÍDE, Rodrigo Williams Rodrigues 09 July 2012 (has links)
Submitted by Samira Prince (prince@ufpa.br) on 2012-10-10T16:50:42Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_ProjetoImplementacaoNodo.pdf: 2052647 bytes, checksum: 8f9cfd77bd747d9ae057a4f5f24659f4 (MD5) / Approved for entry into archive by Ana Rosa Silva(arosa@ufpa.br) on 2012-10-10T17:21:56Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_ProjetoImplementacaoNodo.pdf: 2052647 bytes, checksum: 8f9cfd77bd747d9ae057a4f5f24659f4 (MD5) / Made available in DSpace on 2012-10-10T17:21:56Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_ProjetoImplementacaoNodo.pdf: 2052647 bytes, checksum: 8f9cfd77bd747d9ae057a4f5f24659f4 (MD5) Previous issue date: 2012 / Esta dissertação tem como objetivo principal propor um nodo (ou nó) sensor sem fio para ser utilizado em redes de sensores sem fio, em sistemas de aquisição de dados de extensômetros. O sistema de aquisição para os extensômetros é baseado na ponte de Wheatstone e de modo a permitir várias configurações de extensômetros. O processamento e a comunicação sem fio é realizada pelo ATmega128RFA1, composto por um microcontrolador e um transceiver Rádio-Frequência com o padrão Zigbee. O nodo foi projetado para garantir confiabilidade na aquisição de dados e ser totalmente controlado remotamente. Entre os parâmetros controláveis estão: o ganho do sinal e a taxa de amostragem. Além disso, o nodo possui recursos para efetuar o equilíbrio da ponte de Wheatstone automaticamente. A escolha de seus componentes, baseou-se em critérios relacionados ao consumo de energia do mesmo e ao custo. Foi concebida uma placa de circuito impresso (PCI) para o nodo, e sobre ela foram realizadas estimativas sobre o consumo de energia e valor agregado do protótipo, com o objetivo de analisar a sua viabilidade. Além do projeto do nodo sensor, o trabalho apresenta a proposta de integração do mesmo em uma rede de sensores sem fio (RSSF), incluindo a sugestão do hardware complementar e desenvolvimentos dos softwares. Para os testes do nodo sensor, foi construido experimentalmente um transdutor de força. / This dissertation’s main objective is to propose a node wireless sensor for use in wireless sensor networks, in data strain gage acquisition systems. The acquisition system for the strain is based on the Wheatstone bridge and enables various settings. The processing and wireless communication is performed by ATmega128RFA1, composed of a microcontroller and a radio-frequency transceiver with the Zigbee standard. The node is designed to ensure reliability in data acquisition and be fully controlled remotely. Among the controllable parameters are: the signal gain and sampling rate. In addition, the node has resources to make the balance of the Wheatstone bridge automatically. The choice of components, based on criteria related to energy consumption and cost the same. It was designed a printed circuit board (PCB) for the node, and regarding it, estimates of energy consumption and value of the prototype were made, with the aim of analyzing its viability. Besides the design of the sensor node, the dissertation presents the proposal of its integration in a wireless sensor network (WSN), including the suggestion of complementary hardware and software developments. For testing, a node sensor was constructed experimentally and used a force transducer.
230

Proposition d'une nouvelle méthode d'accès déterministe pour un réseau personnel sans fil à fortes contraintes temporelles

Van Den Bossche, Adrien 06 July 2007 (has links) (PDF)
Aujourd'hui, les technologies de réseaux sans fil (WLAN/WPAN) présentes sur le marché sont nombreuses et globalement complémentaires. Cependant, trop peu d'entre elles proposent de réelles garanties sur la remise de messages dans un temps borné alors que ces exigences sont fondamentales dans le cadre d'une utilisation de type industriel. Dans le cadre de nos travaux, nous proposons une nouvelle couche MAC entièrement déterministe pour un réseau sans fil personnel basse consommation (LP-WPAN) IEEE 802.15.4 présentant des garanties sur le plan temporel.<br />Tout d'abord, un état de l'art est effectué sur les principaux réseaux sans fil existants, les mécanismes de gestion de la Qualité de Service et les méthodes d'accès généralement utilisées. Nous présentons ensuite la technologie IEEE 802.15.4/ZigBee sur laquelle sont basés nos travaux. Cette étude approfondie nous a permis d'identifier certaines imperfections au niveau de la méthode d'accès par rapport aux contraintes temporelles. Nous proposons de combler ces lacunes par la création d'une couche MAC entièrement déterministe dont nous présentons les caractéristiques et les nouvelles fonctionnalités. Plusieurs méthodes complémentaires ont été utilisées pour valider nos propositions : Réseaux de Petri, simulation et prototypage réel. Les résultats obtenus et les analyses de ces trois études sont exposés.

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