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Control and Diagnostic System for I2C Bus
Juhás, Miloš ; Šebesta, Jiří (referee) ; Urbanec, Tomáš (advisor)
The objective of this diploma thesis is design and realization of I2C bus analyzer. I2C bus protocol is briefly described, together with means of connecting devices to the bus. Next the basic requirements for I2C bus analyzer are defined. Then the design of hardware I2C-to-USB converter including block description is proposed. The chapter dedicated to converter firmware describes method of communication with PC, decoding of intercepted commands and principles of master, slave and passive mode of bus monitoring. The last part is focused on operation software and its structure. Described are individual interfaces, most notable classes and default plugin modules.
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RF Generator up to 4.4 GHz with ADF4350
Frydrych, Jiří ; Šádek, Václav (referee) ; Urbanec, Tomáš (advisor)
The aim of this work is design, realization, and measurement of wideband microwave generator, which is based on the ADF4350 frequency synthesizers. The generator uses the principle of mixing, for frequencies up to 2.2GHz. Higher frequencies are obtained through direct channels. The first part describes the theory of phase locked loop . The following section describes the parameters of the ADF4350 and their management. A PCB was also designed to control the generator with Atmel s AVR AT-mega32. The Generator software is written in AVR Studio in C programming language. The realized generator is housed in a stainless steel box and can be controlled using the keyboard and PC.
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FM Transmitter of APRS Telemetry in 144MHz Band
Sabol, Martin ; Špaček, Jiří (referee) ; Urbanec, Tomáš (advisor)
This work deals with analysis of protocol APRS Automatic Positioning System for telemetry. There is analyzed the structure of the most important frames and their application. It discusses the processing of GPS data and subsequent modulation of the selected frequency. This work also describes and discusses the proposed peripheral devices and the used firmware.
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FM Coincidence Detector - Laboratory Equipment
Mlčoch, Jiří ; Urbanec, Tomáš (referee) ; Baran, Ondřej (advisor)
This work is aimed at an analysis of frequency demodulation, design, simulation, and construction of a coincidence demodulator. Chapter 1 explains the basic characteristics of frequency modulated (FM) signals and provides an overview of the required signal bandwidth, the signal spectrum, and the signal-to-noise ratio after demodulation. Chapter 2 describes each type of FM demodulator separately, and it includes all significant types of demodulator for FM radio broadcast. The function of the coincidence demodulator and its characteristics are explained in detail. Chapter 3 contains a theoretical solution of the phase shift network. Calculated values of the circuit elements are verified by simulation with a view to the total harmonic distortion of the demodulator output signal. Chapter 4 describes the front-end circuit of the receiver. Here, the filter design and the mixer circuit description are provided. The final part of the thesis presents the applicable laboratory task.
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Design Rules for Electronic Systems with ATMEL Microprocessors from the EMC Point of View
Kaštan, Jiří ; Svačina, Jiří (referee) ; Urbanec, Tomáš (advisor)
This diploma thesis is dealing with the basic knowledge of the Electromagnetic compatibility. It’s concretely target on electromagnetic interference flowing from the application of electronic gas control by Honeywell company. Author compile the power control board with including software in language C. The next alternates of power control board with the separated microprocessor were designed for the more extended source detection. On these boards there were explored shielding surface features placed directly under the microprocessor. The application reducing the interference was designed in accordance to the rules finding out during this diploma thesis writing.
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High Efficiency Microwave Power Amplifiers - Laboratory Experiment
Gajzler, Jakub ; Svačina, Jiří (referee) ; Urbanec, Tomáš (advisor)
This Diploma thesis deals with methods that increase efficiency of transistor amplifiers. In the first part of the thesis we describe theoretical background of the constructions of power amplifiers. At first we deal with the classical method that is concerned with a change of position of the static operating point. Secondly we cover the multi harmonic manipulation method (MHM). This method is concerned with a proper loading of particular harmonic components and consequential shaping of voltage runs and currents on the collector. In the second part of the work we have constructed the substitutes of particular accesses. Constructed classes are AB, F and FMHM. Basic S parameters and output signal spectrum were measured. We can see from the calculated efficiencies AB = 11%, F = 16% a Fmhm = 18%, big increase of efficiency F and FMHM only by changing output network.
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Microprocessor Controlled Power Measurement System for Frequencies below 10GHz
Klíma, Martin ; Lukeš, Zbyněk (referee) ; Urbanec, Tomáš (advisor)
The aim of this work is to design a microprocessor controlled power measurement system which is based on the logarithmic detector AD8317, then to create a printed circuit board and to test its functioning. The logarithmic detector AD8317 is acceptable for measurement of high frequency signal’s power of the level between approx. –55 dBm and – 3 dBm in the frequency bandwidth of 1 MHz to 10 GHz. Its output provides DC voltage which is corresponding to the decibel-scaled level of the input signal. This is suitable for A/D conversion and digital processing by the microprocessor. The result of the work is a complete measurement system.
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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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