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Current possibilities of data communication via the power network
Jedlička, Tomáš ; Mišurec, Jiří (referee) ; Mlýnek, Petr (advisor)
This thesis is focused on processing, summary information about PLC commnunication and analyzing present issue of data transfer via powerline grids. Teoretic and technical information about PLC communication, advantages, disadvantages, kinds of PLC communication depending on used frequency ranges and also about used modulation techniques are processed in the first part of the thesis. The second part of thesis is focused on analysis information about choice types of modems and companies, which are oriented on PLC technology. Measurements results of broadband PLC communication are evaluated in the third part of thesis with opportunity to extend and modification it. Laboratory measurement of narrowband PLC communication is processed and focused in this part on transmission speed and spectrum of signal. Results of measurement in company ModemTec are summarized in the end of thesis.
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OFDM implementation in FPGA
Horák, Martin ; Fedra, Zbyněk (referee) ; Maršálek, Roman (advisor)
The thesis is focused on designing OFDM modem, which should be implemented into the FPGA device. The advantages of using OFDM signals in order to provide high baud rates together with high multipath immunity has provoked a mass expansion into media systems such as DSL, DVB, Wi-Fi, WLAN, etc. . Thanks to this technology we can quarantee high modulation rates with minimal negative disturbance eects. The rst part is dedicated to characterise OFDM signals, their generation and the algorithm producing the OFDM which is implemented in DSP devices. For the purpose of using the fastest algorithm, the Fast Fourier Transform using Cooley-Tukey algorithm was shown. Before we can implement OFDM modem into the FPGA device, we have to simulate its correct function. Because there is no OFDM analyser available at our departement, its necessary to prove its correct function by simulations. Therefore a large part of this thesis is focused on simulations using Matlab and ModelSim, in order to show comparison between the theoretical, and simulated results. Between the theoretical and practical simulations there is a part which shows the brief characteristics of available FPGA devices. Detailed view is presented just for the Virtex II device, which the implementation is made for. As a suitable FPGA device, we have chosen Virtex II XC2V1000 which is available for students. In the last part the measured results were shown to prove the corect function of the modem. Programming the FPGA using VHDL language is realized in the software ISE Xilinx (distributed in Xilinx software support). All programmed scrits and data used in this thesis are included on distributed media.
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Position monitoring with the help of GPS/GSM modem
Zavadil, Miloš ; Vyoral, Josef (referee) ; Šilhavý, Pavel (advisor)
The first chapter of bachelor thesis is focused on theoretical explanation of the most important terms in Global Positioning System describing basic principles and position monitoring possibilities. The structure of the whole GPS system and its position setting accuracy is described further. The NMEA protocol used for transferring GPS information is shortly mentioned too. The second chapter deals with Open AT platform used for application development. It is a product of Wavecom company. The third thematic unit has already practical character. It shows the results of locating GenLoc25 modem by AT commands and decoding NMEA frame. Three variants of applications developed in Microsoft Visual C++ are described in the last chapter. All of them are used for position monitoring with GPS/GSM modem. The first program has the same functionality as the modem locating by AT commands. It is only for visualization of GPS information in Terminal window. The second application we can consider as the most important in this thesis. It contains all the items from the assignment. Actual data position is automatically sent to FTP server by GPRS transmission. The data are stored on this server. Received data are visualized in web browser by PHP script which is stored on server too. Final application is derived from the second one. The algorithm assumes that data are not sent to server regularly but transmission depends on human factor.
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Cellular Modem Emulator for Acceleration of Embedded System Development
Horký, Vít ; Mrázek, Vojtěch (referee) ; Vašíček, Zdeněk (advisor)
The purpose of this work is to create an emulator intended for testing and development of libraries for communication with cellular modems with support for AT protocol. This emulator is implemented as a python library and supports basic AT commands and GSM multiplexing. Support for testing other devices and libraries is achieved by user specified testing scenarios. By default, support for emulating modem Bg96 by Quectel is implemented but an emphasis is placed on the ability to support other modems.
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Automation of measurement of transmission properties of DSL modems
Pokorný, Lukáš ; Šedý, Jakub (referee) ; Šilhavý, Pavel (advisor)
The work deals with transmission parameters of DSL systems and software development for the automated measurement. The first part is devoted to the transmission medium and modulation techniques. The following describes the detailed functions and features of ADSL2+ modems. Integral part of the work is the overview of the ITU test methodology, together with parameters of test loops and types of interference. Within the automation of measurement are described used Spirent simulators DSL414E and DLS8234 and important communication commands. The practical part is devoted to designing applications for control simulators and software for automated measurement. For implementation of algorithms and creation of graphical interface is used C++ programming language. Finally the results of measuring the transmission properties of ADSL and VDSL systems executed by created application are presented.
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Design of a BPL modem with an ethernet interface
Malček, Ladislav ; Rusz, Martin (referee) ; Musil, Petr (advisor)
The task of the master thesis is the review of selected module PLC Stamp 1200, which provides data communication via power-lines. Subject of the first part is description of PLC communication and its types, especially BPL communication. Afterwards transmission lines, communication interfaces and couplers for injecting the signal into the lines are described. Next, general procedure of design printed circuit boards is presented, followed by specific application rules for prototype BPL modem, especially for RMII and RGMII interfaces. In the second part the design of printed circuit boards for BPL modem is presented. Next, the results of measurement of modem prototype and final device is provided. In the last part of the master thesis, there is a design and results of testing of noise coupler for injection of noise into transmission lines. This device is used for BPL modem testing in worsened conditions.
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Cellular Modem Emulator for Acceleration of Embedded System Development
Horký, Vít ; Mrázek, Vojtěch (referee) ; Vašíček, Zdeněk (advisor)
The purpose of this work is to create an emulator intended for testing and development of libraries for communication with cellular modems with support for AT protocol. This emulator is implemented as a python library and supports basic AT commands and GSM multiplexing. Support for testing other devices and libraries is achieved by user specified testing scenarios. By default, support for emulating modem Bg96 by Quectel is implemented but an emphasis is placed on the ability to support other modems.
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Influence of physical parameters and age of power lines on PCL/BPL performance and reliability
Janás, Jan ; Mlýnek, Petr (referee) ; Benešl, Lukáš (advisor)
With the increasing demands on data transmission, other ways are being sought than standard data transmission via conventional data cables. One of these ways is communication over power lines - PLC or BPL technology. This method of communication is widely used in households, energy, industry and other fields where it is used for data collection, communication, or control of various devices. Before considering the use of BPL technology, it is first necessary to evaluate the considered power line to see if it is suitable and technically competent for this purpose.
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