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THE REDUCTION OF SIGNAL DYNAMIC IN ORTHOGONAL FREQUENCY DIVISION MULTIPLEX SYSTEMS
Urban, Josef ; Lúč, Andrej (referee) ; Galajda,, Pavol (referee) ; Maršálek, Roman (advisor)
This doctoral thesis is focused into the area of multicarrier radio communications systems. These systems are perspective for current and incoming mobile communications and wireless networks. Advantages of multicarrier systems like better multipath propagation resistivity are redeemed by some disadvantages. The high peak to average power ratio of transmitted signal belongs to these disadvantages, for its inconvenience for high efficient power amplification. The thesis concerns with peak to average power ratio reduction methods for OFDM systems, that belongs to the most used multicarrier systems. One of the main objectives is the modification of the existing methods with the intention of complexity reduction. Following subject of interest is the analysis of suitable methods combinations possibilities for more significant peak to average power ratio reduction. One part of this thesis is research of influence of these methods on the OFDM signals with different parameters.
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GSM alarm for motorcycles
Beníček, Martin ; Fedra, Zbyněk (referee) ; Urban, Josef (advisor)
The main target of this work is to design and to implement unfailable safety appliance for motocycles with use any GSM technology. In my masters’s thesis I applied to individaul fields which I had to knows for realization of this work. The introductory chapter tells the reader about evaluation of former semestral projects and about brief description of the realized mechanism. It is followed by descripctoin of principles of communication between PC and mobile phone. The main part of my work is dedicated to application itself. The applicaton is called motoalarm. The last chapter creates description service of localisation mobil phones which is called Kde je... The conclusion includes evaluation of this master´s project and general description of the realized mechanism.
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PAPR reduction in OFDM and simulation in Scilab
Maňák, David ; Maršálek, Roman (referee) ; Urban, Josef (advisor)
Main goal of this dissertation is read over principal and properties of the OFDM modulation. Onward we become acquainted with basic methods for PAPR dynamics reduction in OFDM such as Clipping or Interleaving. Simulation of reduction methods will be realized in Scilab environment, in which are made basic functions for OFDM modulator and demodulator. Furthermore there are created functions for PAPR reduction methods. All established functions are implemented in the GUI.
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Multicarrier modulator and demodulator for software defined radio
Klučka, Jaroslav ; Urban, Josef (referee) ; Maršálek, Roman (advisor)
This thesis deals with computer simulation of the communication chain using the OFDM modulation. In the beginning of my thesis there is a brief description of digital modulations, especially OFDM. The model of the transmitter, radio channel and receiver, including a simple timing and frequency synchronization and equalization is designed and simulated in the Matlab environment. There is a designed communication system implemented into USRP development board in the Simulink environment. The development board could not work simultaneously as a transmitter and as a receiver. Function of the transmitter was verified by measuring on spectrum analyzer. Testing OFDM signal using the arbitrary waveform generator CompuGen 4302 was generated for the verification of the function of the receiver. Testing signal was received and demodulated on the development board which works as a receiver.
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OFDM demodulator implementation in FPGA
Solar, Pavel ; Urban, Josef (referee) ; Maršálek, Roman (advisor)
The master's thesis briefly analyses the principle of OFDM modulation, possibilities of the synchronization and channel estimation in OFDM. The simply model of OFDM system is made in MATLAB. Because of the implementation in FPGA is generated the behavioral description of the OFDM demodulator through the combination of the schematics description and the description in the VHDL language. The ISE development environment is used.
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Vybrané geodetické činnosti při monitoringu a realizaci dálničních mostů
URBAN, Josef
This thesis deals with the monitoring of the bridge object SO211 on the D3 0310/II Hodějovice - Třebonín highway. The observed bridge structure was measured by precise levelling in stages within one year approximately every two months, while it was determined whether there were any limit deviations, therefore a change of position. The work is divided into theoretical and practical parts. In the theoretical part there are described basic information about geodetic devices and there are also explained the measuring methods. The practical part contains a description of the object including how its local measurement network was created. The main part is then the processing of the measured values, which are compared with each other in program Microsoft Excel, where graphs are created for individual stems. Finally, all measured points are evaluated and compared with each other and with the standards for limit deviations.
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History of football club in Kostelec nad Labem
Urban, Josef ; Pokorný, Ladislav (advisor) ; Dlouhý, Martin (referee)
Objektive was to describe the history of the football club Kostelec nad Labem, now TJ Kostelec and the circumstnces under which it originated. Its origins and sport efforts from the beginning to the prezent. I work, besides the introductiion, dividend into two thematic areas: theoretical and practical. The first five chapters focus the theory, the sixth is practical. In the first two chapters set the goals, objectives and hypotheses. The third deals with the characteristis of football. The fourth chapter is devoted to the development of football in the world and in Czech republic. The fifth chapter is the most comprehensive and discusses the origins and history or the football club in that city and its current for mand activities. The six- chapter interview with a football witness, who is also coach youth. This sesction is considered the most important questions are directed and used to verify or reject hypotheses. The work is a compilation charakter and could beneficial both for people who deal with football, but also for those who would like to learn something about the fotmation of football clubs in this country and their beginning.
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Systems for formal mathematics
Kunčar, Ondřej ; Urban, Josef (advisor) ; Štěpánek, Petr (referee)
The Mizar type system is a relatively sophisticated system as it allows for many properties, such as independent types, attributes, overloading, subtyping, structures and many others. All these properties make formalization of mathematics more intuitive in Mizar that in other systems. However, there is a need to verify mathematical results formalized in Mizar in other systems, so that belief in consistency of Mizar system is strengthened. Attempts at reconstruction of this type system in other mathematics formalization systems follow directly from this requisite. The present work seeks to reconstruct Mizar type system in HOL Light system. The basic idea here is to represent Mizar types as predicates in this system (HOL Light). The present work also aims at precise description of relevant parts of Mizar type system. The thesis concludes by reviewing some of the insights that were arrived at in the course of designing and implementing suggested reconstruction.
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Formalization of the deducibility relation of propositional fuzzy logics
Révay, Petr ; Běhounek, Libor (advisor) ; Urban, Josef (referee)
This bachelor thesis presents the formalization of provability relation of fuzzy logic BL in the environment of a mathematical assistant Isabelle/HOL and also the computer-verified proofs of some theorems and syntactic meta-theorems of this logic. It also provides a description of the process of formalization and describes the tools of Isabelle/HOL used in the code by simple examples. The separate chapter is devoted to the introduction to the logic BL. The formalization has been implemented after studying the documentation and choosing of the appropriate methods of Isabelle/HOL. The formalization allows the software to verify the proofs in the axiomatization of BL, and moreover, of the properties of the provability relation itself. Especially, the proof of the local deduction theorem has been formalized as well as the proofs of the theorems of BL, including the derivations of the redundant axioms BL2 and BL3. The major objective of this bachelor thesis is to explore the possibilities of the proof-checker Isabelle/HOL in terms of fuzzy logic BL. With respect to the obtained results the thesis can be used as the starting point of a wider project of formalization of the others fuzzy logics which are based on the logic BL. Powered by TCPDF (www.tcpdf.org)
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Systémy pro formální matematiku
Kunčar, Ondřej ; Urban, Josef (advisor) ; Štěpánek, Petr (referee)
Title: Systems for formal mathematics Author: Ondrěj Kuncˇar Department: Dep. of Theoretical Computer Science and Mathematical Logic Supervisor: Mgr. Josef Urban, Ph.D. Supervisor's e-mail address: josef.urban@gmail.com Abstract: The Mizar type system is a relatively sophisticated system as it allows for many properties, such as independent types, attributes, overloading, subty- ping, structures and many others. All these properties make formalization of mathematics more intuitive in Mizar that in other systems. However, there is a need to verify mathematical results formalized in Mizar in other systems, so that belief in consistency of Mizar system is strengthened. Attempts at recon- struction of this type system in other mathematics formalization systems follow directly from this requisite. The present work seeks to reconstruct Mizar type system in HOL Light system. The basic idea here is to represent Mizar types as predicates in this system (HOL Light). The present work also aims at precise description of relevant parts of Mi- zar type system. The thesis concludes by reviewing some of the insights that were arrived at in the course of designing and implementing suggested reconstruction. Keywords: type system, Mizar, HOL Light 1
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