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Impedance Transformers with Impedance Ratio 1/50 Ohms for Wide Frequency Range
Zachar, Jiří ; Šebesta, Jiří (referee) ; Dřínovský, Jiří (advisor)
One of the aims of this bachelor’s project was to explore possibilities of the design of impedance transformers for a very wide frequency bandwidth (10 Hz – 100 MHz) with the impedance ratio 1/50 . It is not possible to cover this wide frequency band by one transformer, so the design was split into the design of two impedance transformers. The first transformer was realized on the ferrite coil RIK20. The second transformer was realized by with the components T16-1 and TT25-1-kk+ produced by Mini-CircuitsŽ company, and transform impedance directly in a high frequency range. The performance of realized transformers was approved by measuring transformed impedance on their outputs. The frequency band of transformers was determined from these data. Their insertion loss was also measured. The last part of this work was focused on measuring the insertion loss of EMI filters. The main task was to compare the impedance systems 1 /100 and 0,1 /100 and vice versa. The insertion loss was measured for several chosen EMI filters. The insertion loss of all filters reached approximately the same values for both impedance systems.
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Simple Models of EMI Filters
Kostrhún, Lukáš ; Urbanec, Tomáš (referee) ; Dřínovský, Jiří (advisor)
Thesis goal was principles and method insertion Loss Measurement of EMI Filters study in harmony with the technical standard ČSN CISPR 17, theoretical insertion Loss of Filters deduce in symmetrical and asymmetrical connection of impedance system 50 ohms /50 ohms, 0.1 ohms /100 ohms and 1 ohm /100 ohms, and opposite, and with measure values of Filters compare.
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Models of EMC filters
Kejík, Zdeněk ; Šebesta, Jiří (referee) ; Dřínovský, Jiří (advisor)
Basic problems of the EMI mains filter is explained in the introduction of this thesis. These problems appear during the measurement of insertion loss of filters and by design of EMI mains filter. The important problem is uncertainly of the terminating impedances. Eventualities measurement insertion loss of EMI mains filter and motivation of creation filter models are shown. The following part of this project shows the electronic components, from which are realized the EMI mains filter. Parasitic properties of these real devices are also discussed. The circuitry of EMI mains filter is described by the Modified Nodal Voltage Method. The optimization method called Participle Swarm Optimization is introduced, too. Basic principle and terminology are mentioned. The third part of this project is focused on the own filter and spurious components. Influence of own filter and spurious filters components on insertion loss curve are showed. Magnetic factor coefficient k is searched by the optimization method PSO. The last part of this thesis deals with creation of the alternative circuits with spurious filters components. The performances of the alternative circuits were compared with the measured data for symmetrical and asymmetrical measurement setup. The breakages in the insertion loss curve were used for determining the spurious components.
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Measurement of basic parameters of optical and optoelectronic components
Beneš, Pavel ; Látal, Michal (referee) ; Münster, Petr (advisor)
This diploma thesis deals with optical and optoelecronic components. The first part of the work describes the optical paths and methods of their measurement. The second part describes the coupler, circulator and isolator. Further described is a laser diode, a photodetector and a modulator. The third part describes the measurement procedure of the coupler, circulator, isolator, laser diode, photodetector and modulator. The measured values are compared with the catalog values.
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Optimization of EMI filter Circuitry
Surovec, Vojtěch ; Soldán, Josef (referee) ; Dřínovský, Jiří (advisor)
In introduction of work, I presented the state of the art of measuring insertion loss of the EMI filter and the description of individual methods of measuring is also included. After that I dealt with global optimization methods and some of them I theoretically described. Mainly PSO method was studied carefully, and the principle of optimization in details are presented in the thesis, because this method was used for optimization of the filters parameters in the thesis. Next part of work deals with theoretical and mathematical expression of insertion loss of the EMI filters. Due to the mathematical expression of the insertion loss, the values of parasitic elements of given filter have been optimized in different measuring systems. This optimization was applied on synthetic data. By this step the functionality of optimization was proved and also the fitness function has been tuned and optimised. The last part of thesis works with optimization on measured data of given filters. I found out inaccuracy in mathematical expression of given model of EMI filter, therefore it was necessary to come up with the new filter model. The accuracy increases by using the new filter model. In next step the new model was enlarged by new spurious components.
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Model of the metropolitan optical network
Prudík, Jiří ; Hudcová, Lucie (referee) ; Křivák, Petr (advisor)
The purpose of this master’s thesis is foremost to provide a simple guide how to build elements of optical metropolitan area network. The basic model consists to sequence of construction, network topology, passive and active parts. The collection contains examples of alternative technology such as Wireless LAN with different frequency. The optical network construction based on optical cable, fibres, splices, trays, adapters, connectors and active parts for example a lot of media convertor models. After that there are demonstrating type of wavelength division multiplexer used in metropolitan area network – passive planar PCL splitter. One of the passive planar splitter are used to increase optical fibre channel. At the end of the collection a simplified examples of used measurements – optical time domain reflectometry and optical fibre transmission. Contains standard protocols or reflectogram. The conclusion of this thesis summarizes costs of FTTb (Fibre To The Building) model of optical metropolitan area network in Czech republic and future contribution for society.
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Analysis of the Parasitic Bonds in the RFI Filters
Pišťák, Ondřej ; Vyskočil, Pavel (referee) ; Dřínovský, Jiří (advisor)
These diploma thesis deals with analysis of parasitic elements of EMI filters. It is desirable that the attenuation characteristics can be predicted with the help of the known filter’s schematic even at higher frequencies, where the parasitic elements of the passive components have to be taken into account. The analysis also includes the creation of real circuitry of an EMI filter. The component values are estimated according to this basic model.
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Measurement of basic parameters of optical and optoelectronic components
Beneš, Pavel ; Látal, Michal (referee) ; Münster, Petr (advisor)
This diploma thesis deals with optical and optoelecronic components. The first part of the work describes the optical paths and methods of their measurement. The second part describes the coupler, circulator and isolator. Further described is a laser diode, a photodetector and a modulator. The third part describes the measurement procedure of the coupler, circulator, isolator, laser diode, photodetector and modulator. The measured values are compared with the catalog values.
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Simple Models of EMI Filters
Kostrhún, Lukáš ; Urbanec, Tomáš (referee) ; Dřínovský, Jiří (advisor)
Thesis goal was principles and method insertion Loss Measurement of EMI Filters study in harmony with the technical standard ČSN CISPR 17, theoretical insertion Loss of Filters deduce in symmetrical and asymmetrical connection of impedance system 50 ohms /50 ohms, 0.1 ohms /100 ohms and 1 ohm /100 ohms, and opposite, and with measure values of Filters compare.
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Optimization of EMI filter Circuitry
Surovec, Vojtěch ; Soldán, Josef (referee) ; Dřínovský, Jiří (advisor)
In introduction of work, I presented the state of the art of measuring insertion loss of the EMI filter and the description of individual methods of measuring is also included. After that I dealt with global optimization methods and some of them I theoretically described. Mainly PSO method was studied carefully, and the principle of optimization in details are presented in the thesis, because this method was used for optimization of the filters parameters in the thesis. Next part of work deals with theoretical and mathematical expression of insertion loss of the EMI filters. Due to the mathematical expression of the insertion loss, the values of parasitic elements of given filter have been optimized in different measuring systems. This optimization was applied on synthetic data. By this step the functionality of optimization was proved and also the fitness function has been tuned and optimised. The last part of thesis works with optimization on measured data of given filters. I found out inaccuracy in mathematical expression of given model of EMI filter, therefore it was necessary to come up with the new filter model. The accuracy increases by using the new filter model. In next step the new model was enlarged by new spurious components.
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