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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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Data transmission in GPRS and EDGE networks
Slovák, Jiří ; Ries, Michal (referee) ; Hanus, Stanislav (advisor)
The thesis is conceived as a part of the laboratory task innovation in subject Radio and mobile communications. The main part of the project is to create a complex GUI application in MATLAB programming environment that mediates measuring of bitrate in GPRS and EDGE networks, communication with used modem via virtual serial port and consists of other related functions. The problematics is at first described in detail on theoretical basis with special focus on physical layer of mobile technologies mentioned above. In practical part, there are briefly outlined mechanisms that were used during development. The following part consists of a detailed description of the application itself, created using gained theoretical knowledge.
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USB Host with PIC Microcontrollers
Kučera, Pavel ; Janoušek, Vladimír (referee) ; Hanáček, Petr (advisor)
The aim of master thesis is implementation of USB host in a microcontroller PIC. The thesis contains description of ways of peripherals to computer connections with detailed description of USB bus. There are also discussed several approaches in implementations USB host for embedded systems. A concept of layered USB host system is designed on the basis of analysis of the state of the art. Finally, the designed system is implemented in microcontroller. Resulting firmware of development kit is tested on real USB device.
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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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Testing of ZigBee wireless modems
Kasper, Robin ; Molnár, Karol (referee) ; Martinásek, Zdeněk (advisor)
This thesis deals with the testing of wireless radio modems CDX800. Modems communicate in the unlicensed 869MHz band and are based on the ZigBee standard. The first chapter is devoted to the description of this standard. Thesis aims to test the modems according to RFC2544 and RFC1242 recommendations for testing networks, which are discussed in the work. For testing of the network in accordance with those recommendations have been selected hardware testers Trend Unipro GbE. Testers are primarily intended for Ethernet networks, and therefore it was necessary to use converters from Ethernet to serial line which modems use to communicate with other devices. Measurements of the testers were unsuccessful by virtue of inappropriate choice of converters. The work shows potential substitute for these converters. Furthermore, the work deals with testing the modems in terms of radio range on the line of sight and in build-up area. For this purpose was chosen service program Radwin. At the conclusion of the work was created network design for decentralized wastewater treatment for the community Podbřezí from the measured parameters. Designed network is composed of 50 stations and one control center.
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Narrowband data transmission over the power lines
Valenta, Jaroslav ; Mišurec, Jiří (referee) ; Mlýnek, Petr (advisor)
This bachelor´s thesis is focused on narrowband data transmission over power lines. At first are described possibilities of narrowband data transmission over power lines, next the type of noises and then thesis deals with parameters of communication channel. In this thesis are described too modulation, error corection and data encryption for reliable communication. In the last part of thesis are realized practical measuring in laboratory workplace. The influence of data communication on primary function of power lines are tested. In the end are realized measuring of noise influence on data communication.
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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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Application of GPRS module for real-time transmission of JPG files
Rusinský, Jan ; Hošek, Jiří (referee) ; Dostál, Otto (advisor)
This document describes a design procedure of interface between VGA camera and GSM/GPRS modem for displaying JPEG pictures captured by camera on website. Interface is realized by eight-bit micricontroller ATMEL with application written in C language. For picture transfer to server a TCP/IP stack is implemented into modem. The document is divided into two main parts. The first part describes architecture of the system, used components (camera, modem, microcontroller) and electronic circuit design. The second part of the document is focused on the software for the system. Firstly operating system of modem is desribed, OpenAT development environment for modem application design and WIPsoft library, which is used to implement TCP/IP stack. Next is described application for microcontroller which controlls camera and modem. Last part of this document describes server application and web interface.
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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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Monitoring biological activity honeybees
MACHART, Luboš
This thesis deals with monitoring the biological activity of bees. Its main part is to find and investigate the condition of the field and using questionnaire survey. This survey, I applied for a sufficient number of respondents and by its evaluation optimize and proposed appropriate solutions for monitoring the volume of honey produced in the hives. Interview I end-Rolling so that the resulting solution can be as much closer to the market and thus enable monitoring thread hives remotely as many beekeepers. Data transmission equipment so I chose according to clearly defined criteria. The resulting proposal would allow for further refinement into practice and continue research with interesting data.
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