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Implementation of signal detector
Neradilek, Adam ; Sloboda, Šimon (referee) ; Poměnková, Jitka (advisor)
Thesis deals with the description of communication system and its elements. It covers channel coding, signal modulation, transmission channel and its properties. Furthermore, the thesis explains the principle of energy detector and eigenvalue-based detector and a method of evaluating the capability of detectors using ROC curves. Part of the thesis are simulations of the communication system model in MATLAB, evaluating the quality of detection using ROC curves.
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Experimental Platform for Free-Space Optical Communication in Water
Kousal, Martin ; Fedra, Zbyněk (referee) ; Král, Jan (advisor)
For the needs of underwater drones and seabed exploration, a live image from a camera mounted on the drone needs to be transmitted to the operator. Therefore, a hardware platform has been developed to research and experimentally verify the possibilities of cable-free optical communication in an aquatic environment. In this paper, the possibilities of communications in aquatic environments and their limitations are discussed. Furthermore, a communication chain of transmitter and receiver is designed and then simulated in Python. This proposed communication chain is then implemented. The FPGA configuration of the transmitter and receiver is described, and handlers and scripts are created to receive and process the transmitted signal. Finally, real measurements are performed in air and also mainly in a water environment, where the functionality of the whole chain is verified. In the last part of the paper, possible improvements and their impact on the whole platform are outlined.
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Wideband methods of data transmission over power networks
Svoboda, Pavel ; Mišurec, Jiří (referee) ; Zeman, Václav (advisor)
The aim of this work was to peruse and desribe the high-speed data technology communicating over energy network. In this work was investigated broadband system communicating over low power distribution network. The laboratory network was designed for measuring parametres of this communication and performed set of tests. Lended devices were described, properties of technology specification and methods of connection and management were introduced. Management, configuration and measuring over web interface on the NMS device was described and simple dividision into corresponding functional blocks corresponding to structure of web bookmaks was made. Metodology of individual tests, grounded on documentation “recomandation” RFC and on introduced works, was elaboratly described. Used tools, their properties and managements were described. The transmission speed on application and physical layer were followed primarily, frequency dependencies on signal noise ratio and bits per carrier were followed secondary. Measured results from individuals tests were compared among each other and evaulated. This observation leaded into decision on needed criteria for varius application. The suitaibility for integration into communication network for maintaining corresponding QoS was appreised. Testing and chosen types of tests in this project were standardized and integrated into ITU standard. Individual tests are able to compare from the view of their testify charactestic.
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Classification of transmission channels based on speech signal analysis
Báňa, Josef ; Sysel, Petr (referee) ; Atassi, Hicham (advisor)
The thesis examines the impact of VoIP transmission channel characteristics on speech parameters. It seeks ways of emulating properties of a selected VoIP transmission channel and creating a network emulation environment. Several scripts have been created in the Matlab development environment and used to modify and divide a continuous recording into parts identical to the original speeches, before passing through the transmission channel. Subsequently a database of speech recordings is created, as affected by selected characteristics - jitter, bandwidth, loss. Within these databases, symptoms are sought as the most evident characteristics of the transmission channel. Using correlation, symptoms are selected that are best suited for automated determination of the properties of transmission channel characteristics such as jitter, loss and bandwidth.
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DWDM in access networks
Šifta, Radim ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
The aim of this master´s thesis is an explanation of the problem of optical access networks with wavelength division multiplex, main purpose is to demonstrate the difference between simulation and real measurement. The thesis is divided into several basic thematic areas. At the beginning of thesis is outlined the basic division of multiplexing system, there are discussed the basic solutions of wavelength multiplexes and their possible combinations. The next chapter deals with the active elements, which are an essential part of xWDM systems such as optical lasers, detectors and amplifiers. The following chapter is focused on the passive elements, especially on the passive filters, which form a key part of the wavelength multiplex. Methods of measurement C/DWDM networks are discussed in the next part of thesis. The next chapter describes the topology used by active and passive optical networks. Penultimate part of this thesis consists of designs simulated models PON and WDM-PON networks and comparing their transmission parameters. The final part presents the results of practical measurements of experimental optical access network with wavelength division multiplex, the results are simultaneously compared with results of simulations.
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Analysis of the transmission in the mobile digital audio broadcasting
Kresta, Daniel ; Ulovec,, Karel (referee) ; Kratochvíl, Tomáš (advisor)
This thesis deals with an analysis of a system called Digital Audio Broadcast and describes its mathematical model created in MATLAB program. In the first part basic blocks of a transmitter and a receiver are analyzed along with their principles. Then different types of transmission channels for static, portable and mobile receivers are described. The second part contains description of the DAB mathematical model itself. Individual blocks are described in the order of the DAB signal path, from the transmitter through the transmission channel to the receiver side. In this part the graphical user interface is also described. In the final part the results of experimental measurements and simulations are presented.
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Equalization of the transmission channel
Žlebek, Lukáš ; Šilhavý, Pavel (referee) ; Číž, Radim (advisor)
This thesis describes a design of a simulation of transmission of digital information via communication system and equalization of communication function. The layout of communication channel with multiway transmission is described in following part. Next part is about hardware modulator which generate modulated signal which is transmitted via communication channel and after is sampled by A/D convertion card to computer, where is equalizated and demodulated in Simulink. In the last part of this thesis, there is proposal of the laboratory task and its sample solution.
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Measurement of DVB-T transmission over simulated fading channel
Vašut, Jakub ; Kratochvíl, Tomáš (referee) ; Štukavec, Radim (advisor)
The goal of this bachelor’s thesis is to study basic functional elements of coder and modulator of standart DVB-T. Another goal is to study documentation of DVB-T modulator DTA-110T and ASI/SDI adapter DTA-145 by DekTec. Also is described software channel simulator DTC-305 and parameter settings of simulated fading channel. Fading channels are measured and assigned their effect on quality of received DVB-T signal.
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Equalization of the transmission channel
Žlebek, Lukáš ; Šilhavý, Pavel (referee) ; Číž, Radim (advisor)
This thesis describes a design of a simulation of transmission of digital information via communication system and equalization of communication function. The layout of communication channel with multiway transmission is described in following part. Next part is about hardware modulator which generate modulated signal which is transmitted via communication channel and after is sampled by A/D convertion card to computer, where is equalizated and demodulated in Simulink. In the last part of this thesis, there is proposal of the laboratory task and its sample solution.
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Analysis of the transmission in the mobile digital audio broadcasting
Kresta, Daniel ; Ulovec,, Karel (referee) ; Kratochvíl, Tomáš (advisor)
This thesis deals with an analysis of a system called Digital Audio Broadcast and describes its mathematical model created in MATLAB program. In the first part basic blocks of a transmitter and a receiver are analyzed along with their principles. Then different types of transmission channels for static, portable and mobile receivers are described. The second part contains description of the DAB mathematical model itself. Individual blocks are described in the order of the DAB signal path, from the transmitter through the transmission channel to the receiver side. In this part the graphical user interface is also described. In the final part the results of experimental measurements and simulations are presented.
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