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LTE-Advanced/WLAN testbed
Plaisner, Denis ; Staněk,, Miroslav (referee) ; Miloš, Jiří (advisor)
This thesis deals with the investigation and assessment of communication standards LTE-Advance and WiFi (IEEE 802.11n/ac). The EVM error parameter is examined for each standard. To work with different standards a universal workplace have been proposed (testbed). This universal workplace serves for adjusting transmitting and receiving means and for processing signals transmitted and interpreted. Matlab was chosen for this work, through which only control devices such as generators and analyzers from Rohde & Schwarz. This workplace also measures the coexistence of these standards. At the conclusion of this thesis, different coexistence scenarios were designed and evaluated through testbed results.
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Duplex simulation of LTE-Advanced system
Třetina, Vítězslav ; Staněk,, Miroslav (referee) ; Miloš, Jiří (advisor)
Master‘s thesis discusses about the issues of LTE-Advanced networks. The paper is divided into 4 parts. At the beginning describes some differences which are other then are mentioned in previous 2G and 3G networks. Next chapter focuses on the physical layer LTE. It describes the structure of transmission frames, channels and functions of transmission signals. It also describes briefly the function of HARQ process, turbo encoder and rate matcher. The penultimate chapter focuses on the design of the LTE-Advanced duplex simulator. The last chapter summarizes the results of the created round-trip simulator in the Matlab environment.
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Verification of Properties of WiFi IEEE 802.11n
Alexa, Jan ; Miloš, Jiří (referee) ; Kuder, Zenon (advisor)
This bachelor thesis deals with wireless systems of IEEE 802.11 standards. This thesis explains the fundamental terms and principles, which are relating to digital wireless systems. This thesis is structured into four thematic units. The first chapter discusses an introducing with Wi-Fi standard – IEEE 802.11 in general. Second part contains a deeper focus on modern standards 'n' and 'ac', showing the main differences and innovation compared to older standards 'b', 'g', 'a'. Further in this part of the thesis is described using of MIMO technology. The third chapter contains an analysis and description of the application, which is part of the thesis. The fourth part is detailed focused on to the design of laboratory tasks for teaching at the undergraduate level, which demonstrates the use of MIMO technology.
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Modelling of Network Coding in Wireless Networks
Svobodník, Petr ; Miloš, Jiří (referee) ; Kuder, Zenon (advisor)
During data exchange in the Point-to-Point wireless topology, in case where end nodes aren’t accessible directly, a relay is deployed. However, the basic approach to relays – Store-and-Forward – isn’t the way to reach the maximum throughput. Network Coding operation is performed by combining data words (packets) travelling through the network in opposite directions into one packet. End nodes, with knowledge of the data sent, can decode received packet. Packet exchange is then finished in shorter time which results in an increase of network throughput. There are more methods of Network Coding which differ from each other in the time requirements or the ability to work in a noisy channel. In this paper they will be described and compared.
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WiMAX Physical Layer
Víteček, Petr ; Prokopec, Jan (referee) ; Miloš, Jiří (advisor)
This thesis deals with 4G communication system WiMAX and his model of physical layer in MATLAB in uplink direction. In individual parts of this thesis we will have closer look on WiMAX, multiple access scheme OFDMA and OFDM modulation. Further, the physical layer signal processing and as last the model of physical layer in MATLAB. Result of this thesis should be model of physical layer , which will be together with model of radio environment used to calculate graphs of BER depending on S/N ratio. The model should show how is BER affected by different parts of model such as used modulation, code rate of FEC code and used type of interleaving.
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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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Models of Control Channels in the LTE System
Miloš, Jiří ; Wieser, Vladimír (referee) ; Masopust, Jiří (referee) ; Hanus, Stanislav (advisor)
Dizertační práce se zabývá zpracováním signálu fyzických řídicích kanálů systému LTE a vyšetřováním bitové chybovosti při přenosu řídicí informace z vysílače do přijímače v závislosti na podmínkách příjmu. Práce je rozdělena do dvou hlavních částí. První část práce je zaměřena na simulaci přenosu řídicí informace LTE v základním pásmu. Jsou zde prezentovány vytvořené simulátory řídicích kanálů ve směru uplink i downlink. Simulace jsou provedeny pro všechny druhy nastavení systému a základní modely přenosového prostředí. Jsou zde popsány výsledky vlivu použití MIMO technologií na kvalitu příjmu řídicí informace především v únikových kanálech. Druhá část práce je zaměřena na možnost nasazení systému LTE ve sdíleném pásmu ISM (2.4 GHz). Jsou zde představeny základní koncepce použití, na jejichž základě je vytvořen scénář simulací. Kapitola dále popisuje tvorbu simulátoru koexistence LTE a systému Wi-Fi v přeneseném pásmu ISM 2.4GHz. Jsou zde uvedeny výsledky simulací koexistence LTE a rušivého systému Wi-Fi provedených dle vytvořeného scénáře. Výsledky simulací koexistence LTE a Wi-Fi jsou ověřeny měřením v laboratorních podmínkách. Toto porovnání je důležité z hlediska optimalizace simulátoru koexistence. Dle výsledků obou typů simulací a měření jsou stanovena provozní doporučení, která mají přispět k bezpečnému a spolehlivému vysílání a příjmu řídicích informací LTE i při nepříznivých podmínkách příjmu.
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Cryptographic methods of data security
Miloš, Jiří ; Koutný, Martin (referee) ; Lambertová, Petra (advisor)
Bachelor‘s thesis on theme Cryptographic methods of data security consists of three parts. In first part are itemized general theoretical principles, which employs in these sphere. There are also mentioned not only contemporaneous but historical cryptographic standards or algorithms. The second part of these bachelor‘s thesis refer to a possibility of breaking these standards. There are described most applied cryptoanalytics principes and their practical using, especially in the sphere of computer networks and their services. The final part contains a description of the development of simple computer application, which demonstrates the use cryptographic methods in the security packages in personal computer.
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Signal processing in ZigBee system
Miloš, Jiří ; Bradáč, Zdeněk (referee) ; Hanus, Stanislav (advisor)
Master's thesis The Signal Processing in ZigBee System is focused on properties of Physical Layer of ZigBee (standard IEEE 802.15.4 - 2003). The work consists of three parts. The first part contains common view on using and properties of ZigBee. The next part focuses on the Medium Access Control Layer and in detail on the Physical Layer. There described signal processing in the Physical Layer in individual radio bands. The last part of the project contains the process of modeling in the MATLAB for both models of system ZigBee (bands 868/915 MHz and 2450 MHz). The last part of thesis deals with the simulations of BER depending on Carrier-to-Noise Ratio. Also examined the coexistence of systems operating in the same or a nearby frequency band. Based on the results of simulations there are given recommendations for the use of the ZigBee system in minimizing BER.
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