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Design of enterprise IEEE 802.11 wireless networks
Hlavatý, Josef ; Kubánková, Anna (referee) ; Novotný, Vít (advisor)
This bachelor thesis focus on wireless networks standardized as IEEE 802.11 and their use in wide wireless networks. Wireless transmissions and most known accessories of standard IEEE 802.11 and their functions are theoretically discussed in the first part of the bachelor thesis. Next, bachelor thesis takes care of architecture of vast wireless networks, their division into cells and centralized management of cells and individual AP. Further, security and authentication in wide wirreless networks is described. The second part of bachelor work is formed from detailed manual for execution of wide wireless networks, from which laboratory task is built for subject Network Architecture.
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Mobile communication systems with multiple antennas
Teplý, Lukáš ; Maršálek, Roman (referee) ; Klozar, Lukáš (advisor)
This term paper deals with the use of MIMO Technology in wireless systems intended for mobile communication. At the beginning are described the advantages of the MIMO Technology and the scheme of the communication channel. The communication occurs through communication channels where each channel has its own capacity and other parameters which are described in chapter two. The following chapter deals with the use of MIMO Technology in wireless network and with the wireless standards based on it. The next chapter applies the mobile communication standards LTE and LTE-Advanced. Their network is nowadays being built around the world. These standards are much more faster in comparison with the existing mobile network and enable to manage the increasing amount of “clever” telephones and of transmitted data in the mobile network. There are described the transfer framework structures and their transmission by this network. The end of this chapter pursues the network LTE working in the world and the situation in the Czech Republic.
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Verification of Properties of WiFi IEEE 802.11n
Alexa, Jan ; Miloš, Jiří (referee) ; Kuder, Zenon (advisor)
This bachelor thesis is focused on introducing with WiFi standard – IEEE 802.11 in general. A deeper focus is devoted to modern standards 'n' and 'c', showing the main differences and innovation compared to older standards 'b', 'g', 'a'. Furthermore, this work focuses on the use of MIMO technology. The last part is devoted to the design of laboratory tasks for teaching at the undergraduate level, which demonstrates the use of MIMO technology. Part of this thesis is an application that demonstrates the differences between those standards.
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Benchmarking Performance of WiFi Networks
Hrabčak, Miroslav ; Kašpárek, Tomáš (referee) ; Čejka, Rudolf (advisor)
This bachelor project discusses throughput problems of the WIFI networks. Project analyzes typical problems and factors, that affect decrease of their capacity and concentrates on typical problems of their signal path. Describes techniques of monitoring, detection and debugging causes, which affects decrease of network throughput. The project also includes the experimental testing and analyzes of standards 802.11b/g and 802.11n on the labs WiFi network.
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Real bandwidth devices operating on 802.11n
Vágner, Adam ; Reichert, Pavel (referee) ; Münster, Petr (advisor)
Wifi and any other recent wireless technology works in case of correct use. Simultaneously for huge density of wireless networks today is knowledge of this matters necessity. This project is generally about 802.11x standards and focused to 802.11n standard, topologies and implementations of MIMO in advance. Practical part represents measure simulations and few devices demonstrates real radio parameters. Then devices are tested to data efficiency and ping response in ideal environment and also under signal noise present environment. All measured values are compared in tables and graphs separately. Every event contains word rank.
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Spatial Identification Methods and Systems for RFID Tags
Povalač, Aleš ; Carvalho, Nuno Miguel Gonçalves Borges de (referee) ; Polívka,, Milan (referee) ; Šebesta, Jiří (advisor)
Disertační práce je zaměřena na metody a systémy pro měření vzdálenosti a lokalizaci RFID tagů pracujících v pásmu UHF. Úvod je věnován popisu současného stavu vědeckého poznání v oblasti RFID prostorové identifikace a stručnému shrnutí problematiky modelování a návrhu prototypů těchto systémů. Po specifikaci cílů disertace pokračuje práce popisem teorie modelování degenerovaného kanálu pro RFID komunikaci. Detailně jsou rozebrány metody měření vzdálenosti a odhadu směru příchodu signálu založené na zpracování fázové informace. Pro účely lokalizace je navrženo několik scénářů rozmístění antén. Modely degenerovaného kanálu jsou simulovány v systému MATLAB. Významná část této práce je věnována konceptu softwarově definovaného rádia (SDR) a specifikům jeho adaptace na UHF RFID, která využití běžných SDR systémů značně omezují. Diskutována je zejména problematika průniku nosné vysílače do přijímací cesty a požadavky na signál lokálního oscilátoru používaný pro směšování. Prezentovány jsou tři vyvinuté prototypy: experimentální dotazovač EXIN-1, měřicí systém založený na platformě Ettus USRP a anténní přepínací matice pro emulaci SIMO systému. Závěrečná část je zaměřena na testování a zhodnocení popisovaných lokalizačních technik, založených na měření komplexní přenosové funkce RFID kanálu. Popisuje úzkopásmové/širokopásmové měření vzdálenosti a metody odhadu směru signálu. Oba navržené scénáře rozmístění antén jsou v závěru ověřeny lokalizačním měřením v reálných podmínkách.
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Modern wireless technologies - 802.11n
Bednář, František ; Molnár, Karol (referee) ; Skořepa, Michal (advisor)
This work describes new standard 802.11n for wireless network. The work contains two parts: theoretical and practical. Theoretical knowledge and understanding our problems will be used in design and simulation wireless network. Theoretical part will discuss about function and methods, which the standard picking over from older standard 802.11a, 802.11g a about new features, that should raise transmission data rate and throughput on MAC sublayer dramatically. Data rate of networks based on standard 802.11n will be comparable with Ethernet networks. Main features that increase data rate on PHY layer is method of multiple antennas calls MIMO and use 40 Mhz channel. On MAC layer will be add frame aggregation that cause linear dependent of throughput on MAC layer and data rate on PHY layer. In practical part we will pay attention simulation of stream video high definition in wireless network. This part contain design and components configuration in network. We will be able to compare simulation results individual standards, by creation of several duplicate scenarios.
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E-UTRAN Air Interface Description
Opletal, Prokop ; Kejík, Petr (referee) ; Hanus, Stanislav (advisor)
The aim of this bachelor’s thesis was to study a basic principles of wireless system LTE with a view to radio interface. Readers are familiarize with a basic concepts of system within a text, like modulation OFDM, which is principal for LTE technology. Further in text are shortly describe OFDMA and SC-FDMA technologies, which are employ in LTE downlink and uplink. There are also summarize parameters, which radically change a bit rate in LTE systems. In dependence on the theoretic knowledge was designed a model of LTE system in MATLAB. With this model were performed simulations of transmission of LTE signal through the radio channel.
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Localization of a Moving Target using a MIMO Radar System
Šulc, Martin ; Vychodil, Petr (referee) ; Škorpil, Vladislav (advisor)
The aim of this thesis is to estimate parameters of the moving target using different radar configurations. First the Doppler effect and the time delay of the received signal is examined. The investigation of these phenomenons is made for radial and non-radial movement of simple monostatic radar configuration and after that for the bistatic and multistatic MIMO configuration. The ambiguity function is presented for all these configurations. The ambiguity function is then used to estimate target parameters from the received signal. The received signal model and ambiguity function for the monostatic radar configuration is developed using Matlab software. Finally the practical use of these implementations is presented and compared.
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Femto cells in next generation mobile networks
Bernkopf, Jan ; Štencel, Vít (referee) ; Hanus, Stanislav (advisor)
This paper provides theoretical analysis of LTE network and Femto cells. Its presents their modulation and transition techniques, their performance and of course implementation of Femto cells into LTE macro-layer. It also describes potential risk of interference between LTE macro-layer and Femto cells and provides the way how to solve and simulate interference. Finally it states simulation and analysis of model situations.
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