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Analysis and Simulation of the Signals Transmission in the DVB-H/SH Standards
Polák, Ladislav ; Rupp, Markus (referee) ; Grgic, Songa (referee) ; Kratochvíl, Tomáš (advisor)
Tato disertační práce se zabývá analýzou, simulací a měřením zpracování a přenosu signálů digitální televize pro příjem mobilního TV vysílání ve standardech DVB-H a DVB-SH. Tyto standardy vycházejí z předpokladu, že příjem signálu je charakterizován modely přenosových kanálů s vícecestným šířením. Tyto, tzv. únikové kanály, jsou charakterizovány hlavně zpožděním a ziskem jednotlivých cest. V závislosti na dalších parametrech (rychlost přijímače, Dopplerovské spektrum), je možné rozdělit únikové kanály do třech hlavních skupin: mobilní, přenosné a fixní. Dá se předpokládat, že v různých modelech kanálů bude přenášený signál různě ovlivněn. Proto je potřebné najít optimální parametry systémů (DVB-H/SH) pro kvalitní příjem vysílaných služeb mobilní televize, což je hlavním cílem této disertační práci. Pro tento účel byly vytvořeny dvě vhodné aplikace (jedna pro DVB-H a jedna pro DVB-SH) s GUI v prostředí MATLAB, které umožňují simulovat a analyzovat míru zkreslení signálu v případě mobilních, přenosných a fixních scénářů přenosu. Navíc, tyto aplikace obsahují i druhý samostatný simulátor pro nastavení a modifikaci parametrů jednotlivých přenosových cest. Díky tomu je možné zhodnotit vliv parametrů celého systému a kanálových modelů na dosaženou chybovost (BER a MER) a kvalitu přenosu. Ve všech přenosových scénářích (v závislosti na poměru C/N) byly získané, vyhodnocené a diskutované zkreslení signálů. Navíc, u standardu DVB-H, všechny získané výsledky ze simulací byly ověřeny měřením. Rozdíly mezi dosaženými výsledky (simulace a měření) byly rovněž podrobeny diskuzi. Tuto disertační práci je možné rozdělit do čtyř hlavních částí. První část disertační práce se zabývá rešerší současného vývoje v oblasti digitálního televizního vysílání na mobilní terminály ve standardech DVB-H/SH. Na konci této části jsou jasně popsány cíle této disertační práce. Druhá část práce je zaměřená na stručný popis blokového diagramu vysílačů v obou standardech DVB-H/SH. Dále jsou stručně popsány modely přenosových kanálů, které se používají pro modelování přenosu signálu. Stručný popis vytvořených aplikací, i s vývojovým diagramem, které jsou vhodné pro simulaci a analýzu přenosu v DVB-H/SH, jsou popsány v třetí části práce. Čtvrtá a nejdelší část této disertační práce se zabývá vyhodnocením získaných výsledků ze simulací a měření.
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Comparison of compression algorithms for high definition video
Dvořák, Martin ; Polák, Ladislav (referee) ; Slanina, Martin (advisor)
Bachelor's thesis deals with comparison and analysis of various instruments of the present-day compression algorithms used to compress high-definition video. Video sequences require a large amount of memory for their storage and take up bandwidth for their transmission, so it is necessary to compress video signals with regard to the quality of video after decompressing. The work focuses mainly on the differences between the algorithms and overall performance. Part of this work is a compressed video database, comparing the performance of different algorithms and the subjective quality of compressed video.
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Increased power microturbines operating in indirect circulation
Polák, Luboš ; Fiedler, Jan (referee) ; Škorpík, Jiří (advisor)
Turbogenerator unit 100B TGU, produced in the First Brno Engineering Velká Bíteš a.s., works in Brayton indirect circulation. The aim of this work is the proposal to increase performance levels of technological unit in which the micro-turbine is applied. The work presents various ways to increase performance and efficiency of circulation. The possible options are compared with each of the technological and economic terms. Based on these criteria was selected variant feeding additional water into the circulation. For this design was the work of a mathematical model based on, which was established as the economic balance of the selected variants. The thesis also proposes a technological scheme, which is already incorporated the selected variant and an outline of the verification tests.
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Simulation of the DVB-C and DVB-C2 transmission and their comparison
Cibulka, Tomáš ; Hüttl, Ondřej (referee) ; Polák, Ladislav (advisor)
This Master thesis deals with description, analysis and simulation of standards of digital video broadcasting DVB-C and DVB-C2. There is described mainly the transmission system, channel coding, type of modulation and OFDM symbols generation. Furthermore, channel models, used for the exploring of their performances are described too. There was created an application with a graphical interface in MATLAB, which simulates transmission in DVB-C2. Based on simulations there are compared influences of each settings on bit error rate of data transmission for both standards. Finally, obtained simulation results are compared with theoretical values.
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Subjective quality evaluation of video sequences
Krmela, Tomáš ; Fliegel, Karel (referee) ; Polák, Ladislav (advisor)
This master´s work is focused on the comparison of subjective assessment of the quality of video sequences. In this study, data are obtained by hardware and sofware techniques and they are compared. In the introduction, methods of video compressions are described. The main part of this work deals wtih the exploring of different methods of subjective assessment of the quality of video sequences. Finally, obtained results from different methods, are evaluated and discussed.
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Simulation of the DVB-H and DVB-SH Transmission
Arvai, Luboš ; Ulovec, Karel (referee) ; Polák, Ladislav (advisor)
The paper deals with the channel coding and modulation in DVB-H and DVB-SH and with the simulation of the components in MATLAB. In the case of DVB-H the document also discuss the influence of different types of transmission channels on the transmission process. The first part of this work describes the channel coding and inner modulation in DVB-H and DVB-SH. The next part describes applications created in MATLAB for settings and simulation of the transmission in the standards DVB-H and DVB-SH. The last part of this document graphically presents selected results of the simulation of the transmission and discuss them.
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Simulation of the RF Transmission Channel for the DVB-H and DVB-SH
Hrach, Petr ; Fliegel, Karel (referee) ; Polák, Ladislav (advisor)
Project is focused on description DVB broadcasting for hand-held’s. It describes standard DVB-H that is founded on DVB-T and uses its transmission infrastructure. Standard DVB-SH is a hybrid system that adds to terrestrial broadcasting satellite connection. Signal can extend by various environments, therefore it are defined models transmission channel with defined parameters. Simulation of the transmission in both channel are realized in user application created in MATLAB. Finally, obtained results are evaluated and discussed.
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Simulation of the RF transmission channel for the DVB-T2
Strouhal, Adam ; Hüttl, Ondřej (referee) ; Polák, Ladislav (advisor)
This Master thesis is focused on detailed description of the DVB-T2 system. This work deals with the description of the particular parts of models and with typical RF transmission channels for fixed and mobile reception. In order to simulate the impact of the fading transmission channels on the transmitted signal there was developed an appropriate application in MATLAB. The graphic user interface of this application allows set the transmission parameters of DVB-T2 and the parameters of the transmission channels. Results of simulations with various settings are evaluated and compared with the results, obtained from the DVB-T measurements.
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Simulation of multipah propagation of multistate modulations
Polák, Ladislav ; Pust, Radim (referee) ; Šebela, Radek (advisor)
The diploma thesis Simulation of Multipath Propagation of Multistate Modulations is focused on the development of an appropriate algorithm in MATLAB environment, which is capable to simulate the impact of the multipath propagation on received signal (error rate) on the basis of given parameters of the transmission channels. Mechanisms and characteristics of the wave propagation in communication environment, types of digital modulations and their most important parameters are described in the first part of this thesis. The second part is focused on the simulation itself. Created GUI (Graphical User Interface) is able to display constellation diagrams of transmitted and received signals, as well as their bit error rate. It is also possible to compare these data with the data of signal, which is passed by a non-fading channel.
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Ways of radioactive materials saving in the Czech Republic and in the world
Polák, Luboš ; Šen, Hugo (referee) ; Nerud, Pavel (advisor)
Management of spent nuclear fuel and radioactive waste are many. The aim of this thesis was to summarize the attitude of the Czech Republic and the other major countries on this issue. First is given the classification of radioactive waste according to various criteria. Consequently, it is defined and described the fuel cycle, as the largest producer of all types of radioactive waste. Then is analyzed approach of the Czech Republic to the management of all type radioactive waste and the attitude to deep geological repository. At the end are some, in this respect, major countries and their attitude to deal with spent nuclear fuel, radioactive waste and the method of final disposal.
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