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Frequency synthesizer for microwave communication systems
Klapil, Filip ; Vondra, Vlastimil (referee) ; Kasal, Miroslav (advisor)
The main aim of the thesis is to develop a solution of a frequency synthesizer for a microwave communication systems. Specifically, it suggests a design for frequency synthesizer with phase-locked loop. At beginning of the thesis the principle and basic properties of this method of signal generation are explained. Then it is followed by a brief discussion of the parameters of synthesizers and their influence on design. Another part of the work is the analysis of circuit the frequency synthesizer with the phase-locked loop MAX2871, which is followed by a proposal for the design of the frequency synthesizer module hardware. The last part of the work deals with practical implementation, verification of function and measurement of achieved parameters and their evaluation.
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Wideband 6GHz RF Signal Generator
Mička, Josef ; Kubíček, Michal (referee) ; Urbanec, Tomáš (advisor)
The goal of this thesis is a design of a wideband high frequency generator with an adjustable output amplitude. The generator is based on a frequency synthesizer ADF4355. The power level of an output signal is adjustable by an attenuator HMC1119. The created generator is accesisible trough an user-friendly control panel or by SCPI commands. Frequency synthesis can run in an integer mode or a fractional mode. The output signal has a very low phase noise when it is running in the integer mode.
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Design and Simulation of Single Phase Active Rectifier
Bareš, Jiří ; Huták, Petr (referee) ; Klíma, Bohumil (advisor)
This thesis deals with single-phase active rectifier, strategy of control and simulation of its model. In the beginning of this work a principle of rectifier is described along with transistor switching system, which has impact on shape of input current. Dimensioning of rectifier for assembling model and designing of control, including phase-locked loop and regulators follows. In the end assembled model and its simulation is described.
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Model of Three-phase Power Microgrid
Macík, Tomáš ; Cipín, Radoslav (referee) ; Pazdera, Ivo (advisor)
The Diploma thesis deals with control of three-phase active rectifier and a three-phase DC/AC converter. It also explains phase-locked loop principle. The theoretical part including first three chapters lists several control approaches to three phase active rectifier and three phase DC/AC converter. Described control approaches to the active rectifier are control in dq frame and control in dq UVW frame. Listed control approaches to the DC/AC converter include cascaded control structure and a full state feedback control. The practical part is divided into last three chapters and includes mathematical description of phase-locked loop principle, model of active rectifier controlled in dq frame and a model of DC/AC converter controlled both by a cascaded control and a full¬ state feedback. The models are created in Matlab Simulink.
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Design of magnetic bar-code read head
Kadlčík, Libor ; Drexler, Petr (referee) ; Mikulka, Jan (advisor)
Magnetic bar-code is composed from ferromagnetic bars printed on a substrate. The amount of ferromagnetic material is low, therefore reading magnetic barcode requires sensitive methods. Principle of methods of sensing both low-intensity magnetic field (fluxgates) and detecting low concentration of ferromagnetic material (resonant circuit, differential sensor) will be described. There are sensors producing frequency-modulated signal, therefore we focus on frequency demodulators as well. Signal acquired by sensor suffers from convolution distortion, reconstruction methods will be introduced. The assembled device consists of sensing oscillator, frequency demodulator, amplifier and reconstructing circuit. Frequency demodulation is done by phase-locked loop or differential demodulator. Reconstruction is based on detection of inflection points, producing square signal (representing bars of barcode). Design of these blocks is described. The device is able to read magnetic barcodes and reconstruct convolutionary distorted acquired signal. The differential demodulator exhibits low noise and low temperature drift (contrary to phase-locked loop). Signal produced by reading 2 mm wide bars is reconstructed without any problems, bars of width less than 1 mm cause troubles in certain cases (due to high degree of convolution distortion).
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Control Unit for VHF Radio Receiver with Frequency Synthesizer
Sobotka, Martin ; Šebesta, Jiří (referee) ; Vyskočil, Pavel (advisor)
The aim of this work is to propose the involvement of the control unit for receiving VHF radio and its practical implementation. Adding a panel on the appropriate tuner unit leads to a complete receiver to receive radio broadcasts. My work is to focus on two frequency bands: VHF band for broadcasting and VHF band for air radio communication. This paper describes a process of selection of component, their description and integration into a complete circuit, a description of the control program for the microcontroller and a description of control device. Scheme and the draft for the manufacture of printed circuit board is attached.
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Design of low-frequency phase locked loop for sensing applications in low-voltage TSMC 0.18 um process
Svoboda, Marek ; Dvořák, Radek (referee) ; Šotner, Roman (advisor)
The work deals with the design of FM modulation chains and their sub-circuits, which construction is based on analog multipliers produced in the TSCM process 0.18 m 1.8 V. One chain operate with a rectangular carrier and the other one with a harmonic carrier wave. The basic carrier frequency is 100 kHz, and the basic test modulation signal is 1 kHz harmonic waveform. Demodulators are built on the principle of the phase-locked loop, and the aim of the work is to verify the functionality of such a loop and to determine its limiting properties. The work also contains graphical outputs from the Cadence Virtuoso development package, in which all simulations were performed.
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Wideband 6GHz RF Signal Generator
Mička, Josef ; Kubíček, Michal (referee) ; Urbanec, Tomáš (advisor)
The goal of this thesis is a design of a wideband high frequency generator with an adjustable output amplitude. The generator is based on a frequency synthesizer ADF4355. The power level of an output signal is adjustable by an attenuator HMC1119. The created generator is accesisible trough an user-friendly control panel or by SCPI commands. Frequency synthesis can run in an integer mode or a fractional mode. The output signal has a very low phase noise when it is running in the integer mode.
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Model of Three-phase Power Microgrid
Macík, Tomáš ; Cipín, Radoslav (referee) ; Pazdera, Ivo (advisor)
The Diploma thesis deals with control of three-phase active rectifier and a three-phase DC/AC converter. It also explains phase-locked loop principle. The theoretical part including first three chapters lists several control approaches to three phase active rectifier and three phase DC/AC converter. Described control approaches to the active rectifier are control in dq frame and control in dq UVW frame. Listed control approaches to the DC/AC converter include cascaded control structure and a full state feedback control. The practical part is divided into last three chapters and includes mathematical description of phase-locked loop principle, model of active rectifier controlled in dq frame and a model of DC/AC converter controlled both by a cascaded control and a full¬ state feedback. The models are created in Matlab Simulink.
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