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Creation and processing of signal database
Glett, Jiří ; Šebesta, Vladimír (referee) ; Sigmund, Milan (advisor)
The work become acquainted with history and rise databases globally. Construes philosophy structuralization, sorting and purpose using. Work further deal with concrete databases softwares intended directly to processing audio signals. Further treat of programmes that the make possible generation personal database structures. Work deal about SUSAS database and analysing its content. It is created self database of music signals, which includes several musical groups always similar in certain aspect. Speech database contains records from the SUSAS database and records from television programs, reality-shows, sports broadcasts, reports and documents, when speakers are subjected to stress and emotions. The work is a database program that can effectively classify all records and processes. The database can be freely extended. The resulting program was realized into Czech and English version.
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Multimedia support of the course BSIS
Pasečný, Jan ; Šebesta, Vladimír (referee) ; Sigmund, Milan (advisor)
This paper takes aim at creating a consistent form of study materials, supplemented with illustrative examples, for Signals and systems subject. The thesis starts with basic characteristics of acoustic, image, biological and communication signals. Characteristics of linear signals and AD&DA conversion has been added to the next part and to complete the submission, discrete signals follow. Diploma thesis as a whole contains basic theoretical description of problematics, which it tries to supplement with interesting examples, connections, graphs and matlab scripts for illustrative presentation of mentioned problematics.
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Speech signal processing in spectral domain
Pavlíček, Tomáš ; Šebesta, Vladimír (referee) ; Sigmund, Milan (advisor)
The thesis is focused on getting acquainted with methods of adapting speech signals in spectrum domain and with formants. Fist part is dealing with definition of formant, the relation between Czech language and formants, performing formant features and describing the use of formants in practice. This part includes preprocessing of signals before analysis on its own. This work contains a list of the most common methods for counting speech signals spectrum focused on estimation of spectrum by linear prediction. Practical part contains a verification of the most common methods for specifying formants, which are linear prediction coding and Fourier transformation. Next part is dealing with the description of methods used in created program. It also contains the description of functions of this program and the manual for it. In the end of this work the function of created program is verified and specified database is described.
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Demontration System for Speaker Recognition
Šústek, Martin ; Šebesta, Vladimír (referee) ; Sigmund, Milan (advisor)
My diploma theses deals with the problem of the speaker recognition. The basic theory of this problem is described in the text as well as model and implementation of the system for speaker recognition. The scope of the system is to recognize up to three speakers. The theory is based on calculation parameters for speaker recognition and processing of voice. Program is made in Matlab as a independent application and it has got Czech and English interface.
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Switching off of Electrical Tools by Voice
Rozsypálek, Lukáš ; Šebesta, Vladimír (referee) ; Sigmund, Milan (advisor)
In theoretical part Master’s thesis deals with processing acoustic signal before speech recognition. There are described methods of automatic speech recognition and capture attributes. Those methods are short-term energy of signal, short-term autocorrelation analysis, linear predictive analysis etc. In practical part has been created software, which has to switch off of electrical tool, if the keyword “zastav” has been spoken. In the second part of this thesis software has been optimized for work in real conditions (noise generated by electrical tools).
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Analysis of stochastic processes in electronic components
Vlčková, Irena ; Šebesta, Vladimír (referee) ; Zajaček, Jiří (advisor)
The Bachelor Thesis deals with the interference of electronic parts, using of non-destructive analysis for electronic interference in semi-conductive parts and measured samples. The thesis is divided into thematic areas: Interference types; Spectrum of random continuous signals, Spectrum calculation due to the method of periodogram and the method sub-banding coding and following FFT, Apparatus for interference measuring, Results of interference measuring. In the practical part 5 and 6, there are measuring results of chosen electronic parts, transport and interference characteristics and they are compared with theoretical presumptions.
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Assignment of the OFDM signal cyclostationary detector behaviour.
Lehocký, Jiří ; Šimša, Jan (referee) ; Šebesta, Vladimír (advisor)
Master’s thesis belongs to the Cognitive radio network sphere. These networks utilize frequency spectrum more effectively than networks used in present radio communications. The Cognitive radio concept makes coexistence of classic and cognitive radio networks possible. Attention is aimed at spectrum sensing as the key task of the Cognitive radio. Main properties of the cyclostationary detector, as the detector, that reaches high probability of the detection at a very low signal to noise ratio with apriori knowledge of the transmitted signal's cyclic frequency, are examined in this paper. The OFDM signals, that inherit cyclostationarity from cyclic prefix, used in the real systems have been chosen for testing the properties of the detector. The influences of decimation and multipath propagation on the probability of detection are quantitatively expressed. The optimal values for the weights of the multicycle detector are determined.
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Presentation of selected themes of BSIS in PPT-environment
Havlín, Radomil ; Šebesta, Vladimír (referee) ; Sigmund, Milan (advisor)
The bachelors thesis occupy by topics of the course BSIS, which can be presented by the multimedia and animation techniques in the presentation. In the introduction, these topics are given a different method of processing. In most cases, provides a modular solution by demonstration and argued spectrum signal. The chapters describe the operation with one, two signals at the time, the properties of Fourier transform with illustrative demonstration, the correlation with convolution, kvaziperiodické signals and the last chapter the spectrum of selective signals.
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Communication systems based on MB-OFDM
Škapa, Martin ; Šebesta, Vladimír (referee) ; Maršálek, Roman (advisor)
The aim of the Master’s Thesis is to describe ideas of the MB-OFDM principle that represents the possibility of OFDM principle implementation in ultra wideband systems. There are compared physical layers of the IEEE 802.15.3a and the ECMA-368 standard which include the MB-OFDM principle. In practical part of the thesis, there was created a model of ECMA-368 physical layer in MATLAB environment including CDMA access principle. Finally, the MB OFDM system resistance against disturbance and the Peak-to-Average-Power Ratio is analyzed and commented.
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Matched filter
Lehocký, Jiří ; Maršálek, Roman (referee) ; Šebesta, Vladimír (advisor)
This work implies the essential possibilities of spectrum sensing and their use. Main attention is paid to matched filtering as a method achieving high processing gain in a short time. The impact of main parameters on the result of the detection is shown in this work. By analysing the output of detector not only in ideal conditions, but also in real transmission system, the most realibly detectable sequences were identified. Further the possibilities of spectrum sensing by matched filter in OFDM based systems are presented.
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