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Filtration of time series
Pinkava, Jan ; Poměnková, Jitka (referee) ; Maršálek, Roman (advisor)
Thesis is aimed at describing the concepts and basic principles in the economy in gross domestic product. Furthermore it deals with the description of time series, their types, characteristics and the basic classification. A decomposition of time series into thein components is indicated. Another part is a basic description of the most commonly used economic filters - Hodrick-Prescott and Baxter-King. The Christiano-Fitzgerald and frequency-selective filter for short length time series have been practically implemented in MATLAB. The rest of the thesis deals with the application of above mentioned filters to data of Czech Republic, European Union, USA and selected EU countries. Moreover, the correlation between spectral components of the data for selected countries is investigated. KEYWORDS
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Adaptive OFDM
Nowak, Dan ; Valenta, Václav (referee) ; Maršálek, Roman (advisor)
The purpose of this paper is to study the possibilities of the OFDM system adaptive modulation. The study presents mechanism for acquiring the necessary data of every frequency subchannel using pilot signals and application of these data for system adjustment. The paper introduces the water-filling principle for subchannel power allocation on the basis of their SNR and adaptive modulation mechanisms for variety of OFDM usage. These mechanisms are implemented into a MATLAB model. The code is then transformed into graphical representation and using USRP2, the signal is transmitted by real world channel.
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Time-frequency analysis of Czech republic gross domestic product
Tráge, David ; Poměnková, Jitka (referee) ; Maršálek, Roman (advisor)
The aim of this master's thesis is to get familier with problematic and concepts of econometrics (GDP, investment, usage and others). We see into used data mainly their characters and expectations and we discuss possibilities of frequention and time-frequention analysis of these data by Fourier and Wavelet transform. Data of quarter development of gross domestic product in Czech Republic, EU and USA will be analysed by the help of programm MATLAB. Data will be filtered by three ekonomic filters: Hodrick-Prescott, Baxter-King and Christiano-Fitzgerald filters. The aim is to find cyclic elements in developments of GDPs and to suggest an optimal type of analysis.
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Spread spectrum modulator
Lejsková, Alena ; Kováč, Michal (referee) ; Maršálek, Roman (advisor)
This thesis deals with a method of spectrum-spreading of the data signals transmitted in the radio channel. There exist three different ways of spreading application, they uses pseudorandom sequences and also orthogonal sequences. In these systems we can find various kinds of modulations, one of them (Quadrature Phase Shift Keying) is shown at the end of the thesis. Spectrum spreading orthogonal multiplex OFDM is based on this method. The thesis wants to present the principle of the spectrum spreading method and the description of systems, transmitters and receivers that are using this method.
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Modulated signal generator
Melša, Ondřej ; Poměnka, Petr (referee) ; Maršálek, Roman (advisor)
This project occupies with the creation modulated signal generator in MATLAB. There are explicit basic princips of modulation PSK, M-QAM, princip of system with spread spektrum and princip of access OFDM and MC-CDMA. Next there are explicit basic parametres and possibilities configuration of conversion analog PCI card CompuGen 4302, which serves as D/A convertor of signals created by PC.
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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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Fading channel hardware simulator
Pirochta, Pavel ; Kováč, Michal (referee) ; Maršálek, Roman (advisor)
Fading channel is a communication channel that experiences different interference and fading due to multi-path signal propagation. The fading channel is designed by the finite impulse response filter with the time-varying impulse characteristic. The realisation of this filtr is based on the TDL (Tapped Delay Line) model, which simulate signal delay and signal attenuation in each branch. The aim of this thesis is to create the VHDL design of selected fading channel simulator and its description for hardware implementation into the FPGA.
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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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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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