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Application of Synthetic Aperture Radar with Wi-Fi for Indoor LocalizationNafi, Kawser Wazed January 2016 (has links)
Indoor localization is the process of localizing people or objects inside a building in the same way GPS does in an outside environment. In recent years, researchers have successfully achieved improvement in indoor localization accuracy. Still there are many limitations to overcome in performing and achieving good accuracy in indoor localization. The interest in estimating the location of something inside a building with good accuracy is very strong. In this thesis we first propose an indoor localization technique relative to Wi-Fi access points along with a novel heuristic search based algorithm, named MuSLoc. Through simulation and comparative studies, we have shown that MuSLoc outperforms other indoor localization models without the help of fingerprinting or crowdsourcing about the environment. MuSLoc provides almost the same accuracy in LOS (Line of Sight) and NLOS (Non-Line of Sight) environments with regular infrastructure that has recently been provided by smart phones. This model doesn't require any additional hardware support in order to perform well.
Further, we propose another indoor localization based Wi-Fi device tracker model, named MSTracker, which is able to track both moving and non-moving devices inside a building. This model is also free from specialized infrastructure and can perform well without any training data information. Through real time simulation and analysis we have shown that it performs more accurately than other available models.
Through extensive simulations in a real time environment and analysis of performance comparatives with other available models, we have shown that both MuSLoc and MSTracker perform more accurately with COTS than any other method of indoor localization and tracking of objects inside a building. The complete package of MuSLoc and MSTracker can perform perfectly with recently available Wi-Fi modules and smartphones.
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Počítačové sítě, jejich zabezpečení a překonání tohoto zabezpečení / Computer networks, theirs security and overcoming of that securityZikeš, Tomáš January 2013 (has links)
Main goals of this diploma thesis is to chart methods used to secure wireless internet networks a test those methods through attack on access point of wireless network with target to receive password to access this network and decryption of captured packets. For charting of types of security measures used for wireless network, I performed a series of measurements in field on different places in Czech Republic and Germany. Primary purpose of mesurements performed in Germany is caomparison of results from Germany with results from Czech Republic. Also, I tried to crack the security measures i controlled environment. Due to illegality of this experiment I used my own network and network that belongs o one of my friends who agreed with the experiment.In the end is the presentation of results of field measurements and cracking attempts along with some tips for network security.
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Lokalizace objektů v bezdrátové komunikační síti na bázi WiFi / Location Estimation of Objects in WiFi Communication NetworkKohoutek, Jan January 2020 (has links)
The purpose of the thesis is to design and physically implement a system for location of devices in a Wi-Fi based networks deployed in the interior of small and medium-sized enterprises. First of all, the attention is given to the survey of commonly available technologies suitable for determination of the object position. Then, based on these findings, architecture of a location system comprising an array of sensor nodes and central processing unit is proposed. In conclusion, the results are presented and the fulfillment of the requirements is evaluated.
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Podpora kvality služeb v koncových aplikacích / Quality of services support in the end applicationsZelinka, Jiří January 2008 (has links)
The topic of this diploma thesis has been chosen for a discussion and implementation of quality of service on the application and link layer of the OSI model. At the beginning of this thesis the general parameters and basic technologies of the OSI model network layer has been explained. This part was chosen as a resource for explanation of the basic parameters in the quality of services. Basic part is followed by the introduction to the Ethernet technology, which became as a ground for the real model in this diploma thesis. As a part of this section has been written a block which contains a analysis of quality of services in the Ethernet, which means the implementation of IEEE 802.1Q/p. This analysis is followed by structured descrition of the controlling and functionality of quality of services parameters on the link layer with the system tool in the Windows XP, description of Win XP link layer drivers and its modification with system tool tcmon. The end of the theoretical part is represented by introduction to the implementation of quality of service in the wireless networks especially the 802.11e standard. At the beginning of the practical part is specified the description of the topology design which is dedicated to the quality of services implementation. This section is developed to well-founded analysis of applications which were used during topology creating. The last segment of this thesis is dedicated to evolving the practical informations which were obtained during the measurement.
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Zvýšení efektivity handoveru v reálném síťovém prostředí / Increasing the efficiency of the handover in real network environmentMichalec, Richard January 2011 (has links)
The aim of this work is to study methods of handover used in WiMAX and WLAN networks, next suggest the posibility of simulation methods for WLAN handover in the simulation environment OPNET Modeler. This work is focused primarily on obtaining the information about neighboring AP and subsequent selection of a new AP using such information. The work describes in detail each processes solutions that are used to implement newscanning methods
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Gateway pro připojení řídící jednotky ohřívače vody do cloudu prostřednictvím domácí WiFi / Gateway connecting a water heater controller to a cloud through a home WiFiZrzavý, Martin January 2014 (has links)
This master’s thesis is about concept of gateway connection a water heater controller to a cloud through a home Wi-Fi network. In the first part, possible solutions of Wi-Fi gateway are described. The next part describes development of the gateway and its realization.
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Gateway pro připojení řídící jednotky ohřívače vody do cloudu prostřednictvím domácí WiFi / Gateway connecting a water heater controller to a cloud through a home WiFiZrzavý, Martin January 2014 (has links)
This master’s thesis is about concept of gateway connection a water heater controller to a cloud through a home Wi-Fi network. In the first part, possible solutions of Wi-Fi gateway are described. The next part describes development of the hardware and software of gateway and its realization.
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Lokalizace osob v budovách / The localization of the persons in buildingsNoha, Jan January 2016 (has links)
This work presents design of indoor location system. The work is divided into several parts. The first part of this work presents available technologies in section of indoor location system. There are explained principles of elaboration for determine position. There is also description of several manufacturer systems. In the next part is described design of indoor localization system. There are description components of locator and there is described design of the printed circuit board. The last part is concentrating to construction and testing of locator.
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Vers une dissémination efficace de données volumineuses sur des réseaux wi-fi denses / Toward efficient dissemiation of voluminous data over dense wi-fi networksHamidouche, Lyes 21 June 2018 (has links)
Face à la prolifération des technologies mobiles et à l’augmentation du volume des données utilisées par les applications mobiles, les périphériques consomment de plus en plus de bande passante. Dans cette thèse, nous nous concentrons sur les réseaux Wi-Fi denses comme cela peut être le cas lors d’événements à grande échelle (ex: conférences, séminaire, etc.) où un serveur doit acheminer des données à un grand nombre de périphériques dans une fenêtre temporelle réduite. Dans ce contexte, la consommation de bande passante et les interférences engendrées par les téléchargements parallèles d’une donnée volumineuse par plusieurs périphériques connectés au même réseau dégradent les performances. Les technologies de communication Device-to-Device (D2D) comme Bluetooth ou Wi-Fi Direct permettent de mieux exploiter les ressources du réseau et d’améliorer les performances pour offrir une meilleure qualité d’expérience (QoE) aux utilisateurs. Dans cette thèse nous proposons deux approches pour l’amélioration des performances de la dissémination de données. La première approche, plus adaptée à une configuration mobile, consiste à utiliser des connexions D2D en point-à-point sur une topologie plate pour les échanges de données. Nos évaluations montrent que notre approche permet de réduire les temps de dissémination jusqu’à 60% par rapport à l’utilisation du Wi-Fi seul. De plus, nous veillons à avoir une répartition équitable de la charge énergétique sur les périphériques afin de préserver les batteries les plus faibles du réseau. Nous avons pu voir qu’avec la prise en compte de l’autonomie des batteries et de la bande passante, la sollicitation des batteries les plus faibles peut être réduite de manière conséquente. La deuxième approche, plus adaptée à des configurations statiques, consiste à mettre en place des topologies hiérarchiques dans lesquelles on regroupe les périphériques par clusters. Dans chaque cluster, un périphérique est élu pour être le relais des données qu’il recevra depuis le serveur et qu’il transmettra à ses voisins. Cette approche permet de gérer plus efficacement les interférences en adaptant la puissance du signal afin de limiter la portée des clusters. Dans ce cas, nous avons observé jusqu’à 30 % de gains en temps de dissémination. Dans la continuité des travaux de cette thèse, nous discutons de plusieurs perspectives qu’il serait intéressant d’entreprendre par la suite, notamment l’adaptation automatique du protocole de dissémination à l’état du réseau et l’utilisation simultanée des deux types de topologie plate et hiérarchique. / We are witnessing a proliferation of mobile technologies and an increasing volume of data used by mobile applications. Devices consume thus more and more bandwidth. In this thesis, we focus on dense Wi-Fi networks during large-scale events (such as conferences). In this context, the bandwidth consumption and the interferences caused by the parallel downloads of a large volume of data by several mobile devices that are connected to the same Wi-Fi network degrade the performance of the dissemination. Device-to-Device (D2D) communication technologies such as Bluetooth or Wi-Fi Direct can be used in order to improve network performance to deliver better QoE to users. In this thesis we propose two approaches for improving the performance of data dissemination. The first approach, more suited to a dynamic configuration, is to use point-to-point D2D connections on a flat topology for data exchange. Our evaluations show that our approach can reduce dissemination times by up to 60% compared to using Wi-Fi alone. In addition, we ensure a fair distribution of the energy load on the devices to preserve the weakest batteries in the network. We have observed that by taking into account the battery life and the bandwidth of mobile devices, the solicitation of the weakest batteries can be reduced significantly. The second approach, more adapted to static configurations, consists in setting up hierarchical topologies by gathering mobile devices in small clusters. In each cluster, a device is chosen to relay the data that it receives from the server and forwards it to its neighbors. This approach helps to manage interference more efficiently by adjusting the signal strength in order to limit cluster reach. In this case, we observed up to 30% gains in dissemination time. In the continuity of this thesis work, we discuss three perspectives which would be interesting to be undertaken, in particular the automatic adaptation of the dissemination to the state of the network and the simultaneous use of both topology types, flat and hierarchical.
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Trådlös strömning av en ljudsignal till multipla mottagare / Wireless streaming of an audio signal to multiple receiversSandberg, Johnny January 2013 (has links)
I detta examensarbete har det undersökts vilken teknik för trådlös kommunikation som passar bäst att användas då en ljudsignal ska strömmas trådlöst till multipla mottagare. De tekniker som jämfördes var Wi-Fi och Bluetooth. Andra tekniker för trådlös kommunikation, ZigBee, ANT+ och NFC, valdes bort för att deras maximala datahastighet eller räckvidd inte var tillräcklig. 3G och 4G valdes bort för att det krävs en licens för att få använda dessa. Som mottagare skulle i första hand Android- och iOS-mobiltelefoner användas. Dessutom har det undersökts vilka komponenter som behövs för att tillverka en prototyp som ska kunna strömma en ljudsignal trådlöst till multipla smartphones. Slutligen gjordes ett kopplingsschema för denna prototyp. Wi-Fi med WLAN-infrastruktur ansågs vara bäst lämpad för denna applikation. Prototypen som skulle strömma ljudsignalen behövde därför kunna fungera som en Wi-Fi-accesspunkt. Wi-Fi-chipet AR9271 från Qualcomm Atheros valdes att användas som Wi-Fi-sändare för att den har open-source firmware och var lättare att få tag på jämfört med andra liknande Wi-Fi-chip. För att kunna använda Wi-Fi-chipets Linuxbaserade open-source firmware valdes SAM9M10 MCU från Atmel att användas som kontrollenhet då denna kan användas med Linux Embedded. För att digitalisera den analoga ljudsignalen valdes VS1063 Mp3-kodare från VLSI Solution. / This thesis has examined which wireless technology that is best suited for use when an audio signal are to be streamed wirelessly to multiple recipients. The technologies that where compared was Wi-Fi and Bluetooth. Other wireless communication technologies, ZigBee, ANT+ and NFC, were excluded because their maximum data rate or range wasn’t sufficient enough. Since it’s required a license to be allowed to use 3G and 4G, these were excluded as well. As receivers, primarily Android and iOS phones would be used. Furthermore, it has been examined which components that are required for manufacturing a prototype that will be able to stream an audio signal wireless to multiple smartphone’s. Lastly, a circuit diagram for this prototype has been made. Wi-Fi WLAN infrastructure was considered to be best suited for this application. The prototype that would stream an audio signal therefore needed to function as a Wi-Fi access point. AR9271, a Wi-Fi chip from Qualcomm Atheros, was selected to be used as Wi-Fi transmitter because it has an open-source firmware and were easier to come by compared to other similar Wi-Fi chip. To be able to use the Linux-based open-source firmware of the Wi-Fi chip, SAM9M10 MCU from Atmel was selected as control unit since it can be used with Linux Embedded. In order to digitize the analog audio signal, VS1063 MP3 encoder from VLSI Solution was selected.
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