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Turbo-convolution and turbo-block codes
Šedý, Jakub ; Krajsa, Ondřej (referee) ; Šilhavý, Pavel (advisor)
The aim is to explain the Turbo convolutional and block turbo codes and decoding the secure message. The practical part focuses on the design of a demonstration program in Matlab. The work is divided into four parts. The first two deal with theoretical analysis of coding and decoding. The third section contains a description created a demonstration program that allows you to navigate the process of encoding and decoding. The fourth is devoted to simulation and performance of turbo codes.
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Implementing a Video Quality Metric in the H.264/AVC Decoder
Grúbel, Michal ; Číka, Petr (referee) ; Slanina, Martin (advisor)
In this diploma thesis an algorithm for the evaluation of picture quality of H.264-coded video sequences is introduced and applied. As a measure of picture quality objective metric the peak signal to noise ratio (PSNR) is used. While the computation of the PSNR usually requires a reference signal and compares it to the distorted video sequence, this algorithm is able to evaluate PSNR following the coded transform coefficients. Thus, no reference signal is needed.
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Turbo codes and their applications
Ploštica, Stanislav ; Krajsa, Ondřej (referee) ; Šilhavý, Pavel (advisor)
This Diploma thesis aims to explain the data coding using turbo codes. These codes belong to the group of error correction codes. We can reach the high efficiency using these codes. The first part describes process of encoding and decoding. There are describes parts of encoder and decoder. Principle of encoding and decoding demonstrate a simple example. The end of this part contains description of two most frequently used decoding algorithms (SOVA and MAP). The second part contains description of computer program that was made for using as teaching aid. This program was created in Matlab GUI. This program enables to browse error correction process step by step. This program contains graphic interface with many options and display results. In the third part is described program created in Matlab Simulink that was implemented into the TMS320C6713 kit and there is description of measuring procedure. For verification of efficiency of turbo codes was measured any parameters. Some of these parameters are: number of decoding iterations, generating polynoms and using of puncturing. The last part contains measured value and result evaluation.
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Low bit rate voice encoders
Leitner, Jakub ; Mačák, Jaromír (referee) ; Pust, Radim (advisor)
The final thesis deals with coders and voice coders used in speech signal processing. The aim is to create an integral overview of coders and voice coders including a description of their properties, in the second part of the thesis a simulation of algorithms and methods of speech processing is performed in Matlab Simulink program.The basic methods of speech processing and a parametric LPC voice coder were simulated in time domain. In the LPC voice coder model there are implemented the algorithms for obtaining speech segment parameters. These are the algorithm for classification of voiced and unvoiced speech segment, LPC analysis and pitch detection. The output is a parametric signal that enables a receiver to synthesize a speech signal. The appendix 1 contains a list of names of coders or standard numbers of coders and their properties, the appendix 2 includes an overview of speech processing methods.
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Error protection of data transmission using BCH Codes
Kašpar, Jaroslav ; Křivánek, Vítězslav (referee) ; Němec, Karel (advisor)
The thesis Data transmission error-protection with BCH codes deals with a large class of random-error correcting cyclic codes which are able to protect binary data and can be used for example in data storages, high speed modems. Bose, Chaudhuri and Hocquenghem (BCH) codes operate over algebraic structures called Galois fields. The BCH encoding is the same as cyclic encoding and can be done with linear feedback shift register but decoding is more complex and can be done with different algorithms - in this thesis there are two algorithms for decoding Peterson and Berlekam-Massey mentioned. The aim of this thesis is to find BCH code which is able to correct t = 6 independent errors in up to data sequence n = 150 bits, then peruse possible realizations of the codecs and set criteria for the best realization, then design and test this realization. This thesis is split into three main parts. In the first part there are encoding and decoding methods of the BCH code generally described. The second part deals with selecting of the right code and realization. There was chosen BCH (63,30) code and realization with FPGA chip. In the last part is described design of BCH encoder and decoder and compilation in the Altera design software.
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Testing parameters of stepper motors at different microstepping mode
Műller, Jakub ; Chalupa, Jan (referee) ; Klimeš, David (advisor)
This thesis deals with design and construction of test equipment that allows measurements of basic parameters of stepper motors. The first part is devoted to the search about the principle of operation of the hybrid stepper motor. For the analysis engine has been used a mathematical simulation model with real parameters in Matlab/Simulink. The next section is the design of mechanical and electronic form of the test facility with a description of the components used. The last part of this work is focused on measuring the excitation currents and measuring loss of steps at various control modes and microstepping.
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Design of machine tool turntable
Soják, Vojtěch ; Tůma, Jiří (referee) ; Blecha, Petr (advisor)
This bachelor thesis deals with the construction of the rotary table of machine tool. There are all components that are normally used in construction and are available in our market. Also, there are mentioned the most important manufacturers of rotary tables. In the next section is a construction rotary table with indirect drive for vertical milling machine.
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Auxiliary sensorics for unstable balancing vehicle
Solnický, Vojtěch ; Krejčí, Petr (referee) ; Grepl, Robert (advisor)
This thesis continues on successful project of unstable balancing vehicle, which was completed in mechatronics laboratory in last year. The main goal is to supplement vehicle with display device displaying driving conditions. These conditions have to be acquired first from several sensors. Other issues, which are dealt in this thesis, is problem with damage of electronics due to induced voltage in DC motors with permanent magnets, built-in sensor for obtaining information about driver’s presence and logging driving conditions on SD card. In the end there is described implementation of sensors’ output signals verification.
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Manipulator control via microcontroller
Šíl, Petr ; Liška, Radovan (referee) ; Zuth, Daniel (advisor)
This bachelor thesis is dedicated to the control of the manipulator by microcontroller. It is a scale model of the manipulator, which will demonstrate the functions of a similar manipulator in the real time practice. The design of the manipulator consists of two parts, the mechanical part and driving part. In each section were chosen suitable parts to fulfil requirements of desired functions. The functionality, simplicity of manufacturing of all sections, the price and simplicity of control were the main criteria during the design of the manipulator. The system utilised ATmega 128 and development environment AVR Studio 4 to control and test microcontroller ATmega128.
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