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Development of laboratory samples for wireless transmission of electric power based on the magnetic induction
Kopečný, David ; Štěpánek, Jaroslav (referee) ; Krbal, Michal (advisor)
The aim of the thesis is to collect the information about wireless transmission by using magnetic induction and about the current solutions of wireless applications in practice. The thesis includes theoretical basis and information about the current state of wireless power applications. This thesis is also focused on physical principle and draft of possible technical solution. On top of that, it also contains the information from some legislative and hygienic regulations. The second aim is draft of laboratory equipment on the base of gained information and its implementation for purpose of teaching and measuring. For this part was chosen topology of circuit and the specifications of resonance circuits. It resulted in producing a preparation, which consists of the exciter, primary circuit, secondary circuit and a module for measuring. The third aim is to take a measurement on this product and evaluation of characteristic from point of view of efficiency. Measured data were integrated into characteristics. The efficiency of transfer was measured depending on distance and used load. At the same time was also observed work frequency of product. Furthemore, another laboratory product was measured, in which was reached the efficiency more than 51%. The thesis is divided into four main chapters, which can be thematically named as follows: the information, the theory, the draft and the measurement. The first two chapters deal with the theory and characterization of technologies of already applied systems mainly from transport. The following two chapters contain the description of proposal of the product and the very measuring of the efficiency.
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RF power meter
Hlaváč, Štěpán ; Jedlička,, Petr (referee) ; Drexler, Petr (advisor)
This master’s thesis describes various principles of measurement of electromagnetic waves in a free space and on a line. Used sensors and their real parameters are given for every method. The analysis of protections of high-frequency inputs of measuring instruments is done here and the most suitable method and protections of input for realization are chosen. The analysis of design of secondary protection of high-frequency input is done in this project. The protection of input is realized and measured. The suitable method of measurement is chosen as well as the sensor for measurement of power. The block diagram and circuit diagram of the meter of power are designed. According to designed conception the measuring instrument for measurement of power is realized and its single qualities are measured during the realization. In the final part its precision is measured and the evaluation of results is done.
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Methods of acoustic signal sources impedance matching for their further processing
Havelková, Nikola ; Kubánek, David (referee) ; Koton, Jaroslav (advisor)
The purpose of this bachelor thesis is to get acquainted with the theoretical areas related to the issue of impedance matching using the so-called DI boxes. It is mainly the theory of balanced and unbalanced signal, parameters typical for DI boxes (THD, impedance, bandwidth, dynamic range, etc.), knowledge about the transformer, respectively about the coils, or last but not least the issue of operational amplifiers, which is for designing of active DI box absolutely essential. The specifications of the designed DI box based on this theory are subsequently determined and compared with commercially available models. The main target is to achieve better figures or at least get closer to them. Furthermore, the circuit diagram is designed and optimized to achieve predetermined parameters using simulation in the Multisim program from National Instruments. Regarding the resulting specifications of the DI box, a printed circuit board is designed to build a prototype of the device. After its completion, a test gauging using APx525 is done and the results are compared to the target figures.
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NQR spectroscopy - design of measurement methods
Procházka, Michal ; Bartušek, Karel (referee) ; Steinbauer, Miloslav (advisor)
Nuclear quadropole spectroscopy is a modern analytical method for detecting specific solid state materials, e.g. explosives, drugs etc. It uses phenomenon of atomic nucleus called nuclear quadrupole moment. NQR method is very similar to common nuclear magnetic resonance (NMR) that is why major principles are explained using NMR. The thesis deals with basic principle of NQR, its usage for explosives detection and also detection of other chemical compounds and many other useful applications. The thesis deals with specific circuit design, techniques for sufficient sensitivity, impedance matching and circuit isolation. Practical part consists of simulations as well as designs of a few impedance transformers, pi-networks, and coils. Also experimental probe was created. In the last part, NQR workplace was assembled and a few chemical compounds were detected. These were KClO3, NaClO3 and NaNO2 . Finally minimum detectable amount of potassium chlorate as the strongest signal of these was determined.
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Methods of acoustic signal sources impedance matching for their further processing
Havelková, Nikola ; Kubánek, David (referee) ; Koton, Jaroslav (advisor)
The purpose of this bachelor thesis is to get acquainted with the theoretical areas related to the issue of impedance matching using the so-called DI boxes. It is mainly the theory of balanced and unbalanced signal, parameters typical for DI boxes (THD, impedance, bandwidth, dynamic range, etc.), knowledge about the transformer, respectively about the coils, or last but not least the issue of operational amplifiers, which is for designing of active DI box absolutely essential. The specifications of the designed DI box based on this theory are subsequently determined and compared with commercially available models. The main target is to achieve better figures or at least get closer to them. Furthermore, the circuit diagram is designed and optimized to achieve predetermined parameters using simulation in the Multisim program from National Instruments. Regarding the resulting specifications of the DI box, a printed circuit board is designed to build a prototype of the device. After its completion, a test gauging using APx525 is done and the results are compared to the target figures.
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Audio Pre-Amplifier for Laboratory Measurements
Friml, Vilém ; Hanák, Pavel (referee) ; Kratochvíl, Tomáš (advisor)
This thesis deals with a design of audio pre-amplifier with fixed frequency filters and a choice between amplification using integrated circuits and solidstate circuit. The thesis includes a design of attenuation circuit, an amplifier with an integrated circuit, an amplifier with transistors, a RIAA filter, a speech filter, a physiological filter, a rock preset filter and a power supply circuit. The thesis describes design of the circuit board, solution of oscillations of the amplifier with transistors and a measurement of the constructed device. The aim of the thesis is the design and construction of laboratory equipment.
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Design of aparature for RF plasma etching
Bárdy, Stanislav ; Bábor, Petr (referee) ; Mach, Jindřich (advisor)
This bachelor's thesis deals with a design of an ICP (Inductively Coupled Plasma) apparatus. The theoretical part consists of a research of a plasmatic graphene surface cleaning. Next are described plasma generation methods and an RF circuit design. The experimental part deals with a construction of the ICP apparatus and the impedance matching box, an optical diagnostics of a plasma discharge and a measurement of PMMA etching parameters (etch rate, roughness) by a spectroscopic reflectometry and an atomic force microscopy.
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Axisymmetric antennas with metamaterials
Roman, Pavel ; Fiala, Pavel (referee) ; Raida, Zbyněk (advisor)
This project is focused on computer modeling of so-called meta-materials, and on the exploitation of metamaterials in the design of electrically small antennas. For modeling, COMSOL Multiphysics 3.3 was used. Simulations were focused on impedance matching of antennas. Antennas with metamaterials were compared with corresponding conventional antennas without metamaterial layers. The project does not investigate the creation of metamaterials; the project concentrates on their influence on crucial parameters of antennas. Next step this project is focused on optimalization this structure in program Matlab version R2009b. We used optimalization method PSO (swarms of particles) and results are comparing whit results calculating in COMSOL program.
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