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Unit for wireless transmission of electrical energy
Jelínek, Aleš ; Kopečný, Lukáš (referee) ; Žalud, Luděk (advisor)
The aim of this work is to prove the practical applicability of the concept of contactless energy transfer using induction coils. The first part deals with the mathematical model and theoretical proof of the concept being able to work in practice and describes the process of detecting resonance of receiver circuit on transmitter side. Next chapter describes hardware solution of the experimental prototype. The last part contains measurement results of a coupling coefficient of coils and discusses performance and notable features of the prototype.
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Network service testing with WAN network emulator and load simulators
Kocáb, Marek ; Krajsa, Ondřej (referee) ; Novotný, Vít (advisor)
The main task of this thesis was to explore the requirements of different telecommunications services on the network parameter, that are packet delay, packet loss, throughput, jitter. Make to test network service with WAN network emulator and load simulators. Next focus was to explore TCP congestion avoidance algorithms and focus on their throughput. The purpose of the first chapter is to introduce Quality of Service (QoS) for VoIP, video conversation, streaming audio, streaming video and data. The second chapter are to explore various types of delay, that are created from the sender through network device, transmission media to the recipient. The third chapter is to introduce NetDisturb application. It is application, that can emulate real properties of the data network and incoming traffic affect example packet delay, packet loss, bandwidth limit and so on. The key objectives of the fourth and fifth part is TCP protocol and TCP congestion avoidance algorithms. Hier are to introduce TCP protocol basic properties, congestion avoidance mechanisms and analysis of TCP congestion avoidance algorithms. In the practical part are created two laboratory exercises. First laboratory exercise is designed on the implementation QoS for various types of traffic. Second laboratory exercise is focused on the analysis TCP congestion avoidance algorithms and their throughput.
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Automatic configuration of workstations in Cisco academy laboratory
Homolka, Jiří ; Jelínek, Mojmír (referee) ; Komosný, Dan (advisor)
My thesis is focused on the subject of working with distant stations connected with the laboratory control of Cisco academy. Station operations, i.e. laboratory control, have been carried in the environment of the Linux operating systems. The first part of the thesis includes a description of the laboratory, its network architecture and software equipment. Also, the VMware tool is described here. VMware tool is intended for virtualization of computer stations, where the virtual station is created. In this virtual station another operating system may be run. The problems of the command interpreter, its function and possibilities are described here too. Main attention is devoted to the Bash command interpreter and to the creation of the scripts. There are descriptions of the basic tools intended for the network communication with the distant stations. Among the most important parts belong the protected communication, the production of the autentization keys as well as the tool for data recording on more stations at the same time. The description of the access rights to the files and directories is included too. The target of this thesis was to create the scripts in the Bash programming language. The scripts are focused on working with the laboratory stations. They are the sublayers of the common project for this laboratory control. They were developed for the cooperation with the the web interface and MySQL database, created by Bc. Zdeněk Hrabal. The Scripts are intended for the finding information about the stations and virtual systems, and also for the recording images and configuration files of the virtual systems at the distant stations. Recording files and directories is enabled too. The other scripts deal with the erasing and changing of the rights of the particular files and directories. Setting commads with the super-user competence is used at this place. The scripts for the switching on and off the laboratory workstations were created too. To solve the problem described above I chose to develope more scripts. Each of them subserves the particular part of the task. The form of the input and output data of the scripts was select with the reference to the cooperation with the web interface and database. The data are implemented by the form of the input and output files. The output information and the process of the carried operations are displayed through the web interface. The scripts together with the web interface are placed and run from the school server adela.utko.feec.vutbr.cz. In the thesis the settings of the access privileges for the current directories and the files of virtual systems and scripts are presented too.
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RF channel simulation in the MATLAB environment
Daďa, Petr ; Kratochvíl, Tomáš (referee) ; Štukavec, Radim (advisor)
Subject of this thesis is elemental description of DVB digital television and digitalization process of its terrestrial transmission according to DVB-T standard. The thesis characterizes in detail RF transmission channels used for wireless distribute of television. These channels ale mathematically described and their effect to OFDM signal is simulated in the MATLAB environment. It was created application with graphical user interface by this environment. Using simple setting of DVB-T and transmission channel parameters in the application user can simulate selective fading. Results of simulations with various settings are compared and analysed.
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Patient data trasfer over GSM
Pavliš, Jaroslav ; Dlouhý, Jiří (referee) ; Švrček, Martin (advisor)
This diploma thesis is concerned with possibilities of patient data transfer from a pacemaker or implantable cardioverter-defibrillator to physician over GSM. Theoretical part describes options of data transfer in GSM networks, data appropriate for sending and a structure of message is proposed. A device, that is able to send medical data in a form of SMS messages is designed and constructed. The device uses a Freescale MC68HC908GP32 microcontroller, character display with a Hitachi HD44780 controller and a cell phone Sony CMD-J70. The program for microcontroller is written in assembler for HC08. For tabular view of received messages, an application software for PC was created.
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Methods of interleaving data
Soudek, Michal ; Němec, Karel (referee) ; Křivánek, Vítězslav (advisor)
The initial part of my work is dedicated to overall introduction into the transmission systems and its categories. Further the work is focused on dividing of security codes which are used for transmission systems. In the next chapter is analyzed the problems of error origin, mathematical transcription of errors, categorizing of errors which can generate during transmission. The following chapter deals with description of convolutional codes describing security against errors, principle of serial consecution interpretation on parallastic consecution and visa versa. Here is outlined problems of convolutional codes input. In the next part are mentioned three convolution codes which are used for security against burst errors. In the next chapter is mentioned problems of message interleaving and description of used methods, how they originate and detailed description, how the errors are eliminated with the help of long segment interleaving. In the next chapter are described techniques which are used for clustered errors suppression. The last chapter is dedicated to the practical part of my thesis. There are detail descriptions and simulation techniques how the security of non-secure section is developed, transmission on line, burst errors induction on transmitted secure data and consecutive amendment or clustered errors division in transceiver. For the simulation there were utilized three convolutional codes for clustered errors amendment and two interleaving techniques.
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Converged solution of speech services
Mácha, Tomáš ; Kovář, Petr (referee) ; Novotný, Vít (advisor)
Development in VoIP technology is connected with the rapid growth of quality and data rate of the Internet connection. The application of the VoIP technology has become one of the key areas in telecommunication and networking. The main task of this thesis was to explore the questions of IP telephony and voice transmission over data networks according to H.323, SIP and Cisco architectures. Next focus was on designing and implementing experimental workplaces of mentioned architectures and their converged solutions. The purpose of the first chapter is to introduce the theory background of architectures required for implementation of real-time services in data networks and their comparison. The key objectives of the second and third part are to design and implement experimental workplaces containing signaling and proxy servers and hardware or software IP phones of several architectures. Illustration examples of different network topologies are included to demonstrate designed and realized VoIP solutions. Several tests of established communication are done using a packet analyzer. These tests examine duplex data transmission over IP. This article also contains two laboratory exercises designed according to gained practical experiences. The laboratory exercises provide an overview of theory and clearly indicate the possibilities of IP telephony.
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Communication system for the blind - the fixed part
Botko, Ondřej ; Koton, Jaroslav (referee) ; Herman, Ivo (advisor)
The thesis deals with problems of navigation blind in buildings, where is not possibility navigation by GPS (Global Positioning System). This thesis contain resolution through the use of communication units, placed in floor of buildings. This comunication units, equipped with receiver and transmitter, can give direction for blind by send own identification to transceiver in speciál stick (the thesis does not contain solving of the stick), which can information blind of position. Two comunication unit solution are available, that differs by using component part. The main difference is in use control unit of circuit. First circuit use as control unit ATAR862-3 (microprocessor and transmitter in one case) and the second one use microprocessor ATmega 8L. Both component made by Atmel corporation. Circuit with ATmega 8L is more exacting on curent consumption, but solving this problem is available and communication unit has low pretensions and long life. The part of thesis is program, which solving communication protocol for no-problem communication between unit in floor and special stick.
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Tuner for UHF Receiver with Low Power Consuption
Kaštánek, Martin ; Vágner, Petr (referee) ; Urbanec, Tomáš (advisor)
The purpose of this work was to make a proposal for input parts of receiver for band 430 to 440 MHz. A model of chosen semiconductor triode BFP540 was created in simulation software. Possibilities how to decrease consumption of this semiconductor triode, keeping the profit, were investigated through the simulation.In compromise consumption, keeping the profit of the amplifier - an optimal operating point for this semiconductor triode UCE = 1,2 V and IC = 2 mA was found. It was tested through the testing wiring with noise microstrips conformity. Ascertained knowledge was used for construction of tuner for UHF receiver. An operating point of input amplifier of UHF receiver was owing to power supply amplifier forced for bigger effectiveness to UCE = 2,65 V and IC = 2,0 mA. Suppression of mirror frequency is provided with Helix filter of the third order, because of intermediate frequency 10,7 MHz. Mixing on intermediate frequency is made again by semiconductor triode BFP540. Selectivity of receiver is provided with intermediate frequency crystal filter 10,7 MHz with bandwidth 15 kHz. Designed input part enables reception of SSB, FM and digital types of modulation.Bandwidth intermediate frequency exit is adapted to this request To receive particular modulation , it is necessary to complete intermediate frequency signal way with appropriate intermediate frequency filter.
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