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Analýza multicastových protokolů pro WSN / Analysis of multicast protocols of wirelles sensor networkKrajíček, Tomáš January 2011 (has links)
This work deals with the issue of multicast traffic over ZigBee wireless network and implementation of corresponding protocols in to MATLAB background, further with realisation of multicast data transmission, consequential energy performance evaluation and comparation of particular protocols.
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Zabezpečení perimetru v extrémních podmínkách s využitím senzorových sítí / Protecting the perimeter in extreme conditions, using sensot networksDavid, Jakub January 2013 (has links)
This master thesis deals with the theoretical analysis of wireless sensor networks, a description of selected types of sensors, listing their features and principle of operation for intrusion detection perimeter. Then there is described design and implementation of a wireless sensor node for intrusion detection perimeter usable in wireless sensor networks.
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Bezdrátový hlasovací systém založený na IEEE 802.15.4/Zigbee / Wireless Voting System Based on IEEE 802.15.4/ZigbeeAlbrecht, Pavel January 2010 (has links)
In the work, a detail description of the wireless IEEE 802.15.4/ZigBee protocol is presented along with the architectural design of the wireless voting system based on the mentioned technology. The voting system proposed in the work is based on the Freescale's 1321xNSK development kit. The problems related to the design and implementation of the system by means of the kit as well as the problems related to the record-management scheme using the application server, the data backup method and web-export functions including the views are described in the work. At the end of the work, the proposed system is analyzed from several points of view and its main characteristics are summarized.
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Bezdrátově ovladatelné střelecké stanoviště / Wireless Controllable Shooting EmplacementOujezdský, Tomáš January 2008 (has links)
The main purpose of this project is to design and implement a system for controlling targets on a shooting range. This consists of the main control unit and some motor-turning targets. Both control unit and targets are battery powered and use wireless data transfer. This work describes the selection of the proper platform for wireless communication and design of the hardware and software part of the system in relation to low price and high reliability of the equipment. The conclusion of this work should be the system for practical use.
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Technologie senzorových sítí / Technology of Sensor NetworksKoval, Miroslav Unknown Date (has links)
This diploma thesis deals with sensor networking technology, namely about ZigBee. This work consists of two parts - teoretical and practical. The teoretical part is created by some chapters which describe protocols and standards which compose a bases to ZigBee technology. Some parts of this chapter compare ZigBee network with the other wireless solutions and deals with their features. Practical parts is based on properties of available ZigBee devices and summarize communication among sensor network nodes, own ZigBee application, application gateway design and its implementation for ZigBee network monitoring and control from Internet. The last chapter is devoted to discusion about problems and their solutions alternatively about suggestions of next study and improvement this project.
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OPNET Based Design and Performance Evaluation of ZigBee NetworksNurubhashu, Mabusubhan Vali 12 1900 (has links)
ZigBee is a substandard of IEEE 802.15 family that is specially designed to take care of factors such as power, data rate and area that primarily affect network performance. This has controlling and monitoring capability, which finds potential applications in different sectors. ZigBee allows the concept of hybrid networks and mobility. A comprehensive analysis of ZigBee networks was carried out by constructing and simulating the networks to evaluate the performance in terms of throughput, delay, network load, and packets dropped. This research is aimed at evaluating the effect of network topology on the system performance. A careful review of simulation platforms brought the conclusion of using OPNET Modeler which has the required frame work. Different network topologies of simple and hybrid were built and simulated. Throughout the simulations, the best-case scenarios were drawn to the conclusion by the graphical analysis of parameters of evaluation. Mobile networks were constructed and simulated to investigate the effect of mobility on communication.
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Receiver-Assigned CDMA in Wireless Sensor NetworksPetrosky, Eric Edward 23 May 2018 (has links)
A new class of Wireless Sensor Networks (WSNs) is emerging within the Internet of Things (IoT) that features extremely high node density, low data rates per node, and high network dependability. Applications such as industrial IoT, factory automation, vehicular networks, aviation, spacecraft and others will soon feature hundreds of low power, low data rate (1-15 kbps) wireless sensor nodes within a limited spatial environment.
Existing Medium Access Control (MAC) layer protocols, namely IEEE 802.15.4, may not be suitable for highly dense, low rate networks. A new MAC protocol has been proposed that supports a Receiver-Assigned Code Division Multiple Access (RA-CDMA) physical (PHY) layer multiple access technique, which may enable higher network scalability while maintaining performance and contributing additional robustness.
This thesis presents a comparison of the contention mechanisms of IEEE 802.15.4 non- beacon enabled mode and RA-CDMA along with a Matlab simulation framework used for end-to-end simulations of the protocols. Simulations suggest that IEEE 802.15.4 networks begin to break down in terms of throughput, latency, and delivery ratio at a relatively low overall traffic rate compared to RA-CDMA networks. Results show that networks using the proposed RA-CDMA multiple access can support node densities on the order of two to three times higher than IEEE 802.15.4 within the same bandwidth.
Furthermore, features of a new MAC layer protocol are proposed that is optimized for RA-CDMA, which could further improve network performance over IEEE 802.15.4. The protocol's simple and lightweight design eliminates significant overhead compared to other protocols while meeting performance requirements, and could further enable the deployment of RA-CDMA WSNs. / Master of Science / Factories, automobiles, planes, spacecraft and other systems in the future will require hundreds of sensors within a relatively small area for data gathering purposes. The sensors, which form Wireless Sensor Networks (WSNs), must have some method of wireless communication that allows each of them to transmit information when needed without obstructing other sensors’ transmissions. Wireless communication protocols provide a method for doing so. Some recognizable examples of wireless communication protocols include Bluetooth, WiFi, 3G and LTE.
For WSNs in the future, the industry’s leading candidate protocol is called IEEE 802.15.4, but it may not be most suitable because it is known to break down as large amounts of sensors are added to its networks. Because of this, a new protocol has been proposed around a channel sharing technique called Receiver-Assigned Code Division Multiple Access (RACDMA), which uses a different strategy to efficiently distribute network resources among sensors.
This work analyzes the differences between IEEE 802.15.4 and RA-CDMA, focusing specifically on how each protocol allows sensors to transmit without conflicting with one another. A simulation framework is introduced for complete simulations of each protocol. The result of the simulations shows that IEEE 802.15.4 breaks down in dense sensor networks. RACDMA, however, is able to support very large networks, on the order of two to three times the size of IEEE 802.15.4. This result could be an enabling technology for large wireless sensor networks in the future.
Additionally, a new protocol optimized for RA-CDMA is presented. Its simple design could further enable the deployment of RA-CDMA WSNs.
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Système embarqué autonome en énergie pour objets mobiles communicants / Energy self-sufficient embedded system for mobile communicating objectsChaabane, Chiraz 30 June 2014 (has links)
Le nombre et la complexité croissante des applications qui sont intégrées dans des objets mobiles communicants sans fil (téléphone mobile, PDA, etc.) implique une augmentation de la consommation d'énergie. Afin de limiter l'impact de la pollution due aux déchets des batteries et des émissions de CO2, il est important de procéder à une optimisation de la consommation d'énergie de ces appareils communicants. Cette thèse porte sur l'efficacité énergétique dans les réseaux de capteurs. Dans cette étude, nous proposons de nouvelles approches pour gérer efficacement les objets communicants mobiles. Tout d’abord, nous proposons une architecture globale de réseau de capteurs et une nouvelle approche de gestion de la mobilité économe en énergie pour les appareils terminaux de type IEEE 802.15.4/ZigBee. Cette approche est basée sur l'indicateur de la qualité de lien (LQI) et met en œuvre un algorithme spéculatif pour déterminer le prochain coordinateur. Nous avons ainsi proposé et évalué deux algorithmes spéculatifs différents. Ensuite, nous étudions et évaluons l'efficacité énergétique lors de l'utilisation d'un algorithme d'adaptation de débit prenant en compte les conditions du canal de communication. Nous proposons d'abord une approche mixte combinant un nouvel algorithme d'adaptation de débit et notre approche de gestion de la mobilité. Ensuite, nous proposons et évaluons un algorithme d'adaptation de débit hybride qui repose sur une estimation plus précise du canal de liaison. Les différentes simulations effectuées tout au long de ce travail montrent l’efficacité énergétique des approches proposées ainsi que l’amélioration de la connectivité des nœuds. / The increasing number and complexity of applications that are embedded into wireless mobile communicating devices (mobile phone, PDA, etc.) implies an increase of energy consumption. In order to limit the impact of pollution due to battery waste and CO2 emission, it is important to conduct an optimization of the energy consumption of these communicating end devices. This thesis focuses on energy efficiency in sensor networks. It proposes new approaches to handle mobile communicating objects. First, we propose a global sensor network architecture and a new energy-efficient mobility management approach for IEEE 802.15.4/ZigBee end devices. This new approach is based on the link quality estimator (LQI) and uses a speculative algorithm. We propose and evaluate two different speculative algorithms. Then, we study and evaluate the energy efficiency when using a rate adaptation algorithm that takes into account the communication channel conditions. We first propose a mobility-aware rate adaptation algorithm and evaluate its efficiency in our network architecture. Then, we propose and evaluate a hybrid rate adaptation algorithm that relies on more accurate link channel estimation. Simulations conducted all along this study show the energy-efficiency of our proposed approaches and the improvement of the nodes’ connectivity.
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The Smart Home From a Security PerspectiveChristensson, Daniel, Eriksson, Emelie January 2019 (has links)
Based on the fact that many electronic devices are digitalized in our world in order to facilitate our lives, there is a large potential for development in the home. Smart Home solutions are giving us the opportunity to control and manage for example alarms, electricity and surveillance but the technology's rapid improvement paves the way for issues related to security. The objectives for this work will bring up common communication technologies, security and vulnerabilities in the context of a Smart Home and what could be done for future work. In order to investigate the objectives, a literature study has been conducted together with an experiment. The experiment result exploits a weakness in a common Smart Home technology used in the network enable devices in the form of threats and vulnerabilities. In order to mitigate and minimize threats and vulnerabilities one conclusion is that a security policy could be produced. This security policy should provide the user with good practice of how to manage security in order to mitigate vulnerabilities and threats within the Smart Home.
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Propositions pour un protocole déterministe de contrôle d'accès et de routage avec économie d'énergie dans les réseaux ZigBeeFrancomme, Jackson 24 June 2008 (has links) (PDF)
Le développement des technologies de réseaux de capteurs incite les industries à envisager des alternatives réduisant les coûts et la complexité tout en améliorant la fiabilité. Parmi les solutions sans fil actuelles, la technologie LP-WPAN IEEE 802.15.4/ZigBee dispose des mécanismes et des garanties nécessaires pour une utilisation industrielle. Nous proposons des mécanismes de synchronisation entièrement déterministe permettant l'utilisation du standard IEEE 802.15.4 en mode balisé dans un réseau maillé, ainsi qu'une méthode de routage adaptative « AODV en » pour les messages transmis dans un réseau étendu. En premier lieu, nous analysons la technologie IEEE 802.15.4/ZigBee, plus particulièrement sa capacité à conserver son comportement déterministe et économe en énergie dans une architecture de réseau maillé. Cette étude met en évidence plusieurs insuffisances du standard. Notre contribution consiste à palier à ces manques par une synchronisation centralisée réactive aux changements de topologie, esquivant les collisions de balises et de GTS. Ces modifications seront apportées au niveau de la sous-couche MAC. En second lieu, aucun des protocoles de routage (couche 3 du modèle ISO) actuellement les plus utilisés, ne prennent en compte simultanément les critères indispensables au contexte des communications dans un environnement industriel à fortes contraintes sur la consommation et sur le temps. Nous proposons un mécanisme de routage réactif adaptatif recherchant les routes optimisant la durée de vie des noeuds du réseau contraints énergétiquement, et basé sur l'optimisation conjointe du délai et de la consommation. Pour cela, nous avons analysé et évalué la consommation de chacun des noeuds sans fil autonomes utilisant le standard. Nous avons ainsi proposé des informations de délai et de niveau de charge de la batterie de chacun des noeuds, prises en considération dans notre mécanisme de routage adaptatif. L'ensemble de nos propositions sont validées en utilisant diverses méthodes dont les réseaux de Petri temporisés, la simulation et le prototypage. Les résultats obtenus sont exposés à la suite de chacune de nos contributions.
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