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Verification of parameters of passive optical components on short wavelengths
Látal, Michal ; Filka, Miloslav (referee) ; Vojtěch, Josef (advisor)
Semestral thesis deals with the basic theoretical knowledge in the field of optics, light propagation and optical fibers. It describes in detail the optical transmission system and its associated issues, such as the attenuation of optical fibers or differently caused dispersion. The main part of this work is a description of each passive optical elements, their production technologies and applications in optical communications. Within the optical connection its radiation sources and detectors of optical radiation are explained. The last practical part is focused on the measurement of insertion loss provided by passive optical components.
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Polarization in optical fiber
Bilek, Maroš ; Dejdar, Petr (referee) ; Münster, Petr (advisor)
In the theoretical part of the the bachelor's thesis, the first part is devoted to the analysis of the spread of the light beam in the fiber, the parameters of light and various types of fibers. Subsequently, the phenomenon of polarization, its conditions, methods of depiction and writing are described in detail. Furthermore, the issue of polarization mode dispersion (PMD) is explained. Bindings, differential group delay and PMD measurement methods are described. The practical section of the thesis describes the methods and procedures for measuring polarization and polarization mode dispersion. The EXFO FTB-200 measuring platform was used to measure PMD and was equipped with a module for PMD/CD measurement. A polarimeter in combination with a polarization analyzer was used to measure polarization. As part of the long-term measurements, the EXFO FTB-200 measuring instrument was reused in the case of PMD. In the case of polarization measurements, a combination of polarimeter and balance detector was used. Finally, the results of both short- and long-term measurements are displayed. The results of short-term polarization measurements are shown in the form of both, a Poincaré sphere and a polarizing ellipse with a calculated azimuth and ellipticity. Long-term measurements are in the form of graphs that show changes in polarization rotation rate over time. From the displayed results, the dependency of polarization and therefore PMD on the environmental surroundings is concluded.
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Solving problems of CD and PMD in optical networks
Motúz, Rastislav ; Šifta, Radim (referee) ; Filka, Miloslav (advisor)
The aim of this bachelor’s thesis is to analyse dispersions which are affecting a high-speed transfer in optical systems. It is focused on chromatic – CD and polarisation mode – PMD dispersion. It is devoted to definitions, limit values, methods of measurements and compensation methods against disturbance to the final quality of transmission. The thesis is divided into the three-chapter long theoretical part and the practical part which contains two chapters. The results of the extensive experimental measurements done by CD/PMD tester – modular platform EXFO FTB-200 are stated in the practical part and partly in the Appendix too. The output of the measurement confirms the theoretical assumptions stated in the theoretical part and thus proves the aim of the thesis to be achieved.
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Carbon Fibre Composite Materials
Mikula, Martin ; Molliková, Eva (referee) ; Němec, Karel (advisor)
In the first part of a Bachelor's work there is a general introduction with composite materials. These materials are seperated on the basis of matrix kind. The production of composite materials is described as well. The second part is focused on the carbon fibre materials in more detail. The application of composite materials in aviation industry is in the third part of the Bachelor's work.
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The Optical Link Error-Rate Determination
Joch, Antonín ; Kapoun, Vladimír (referee) ; Kyselák, Martin (advisor)
The master thesis discusses physical causes of light polarization and problems brought by nascence of Polarization Mode Dispersion (PMD). These problems occur especially by high speed systems on optical cable traces. The thesis deals with actuation of transmitted signal by influence of Inter Symbol Interference and it also deals with methods for its measuring and compensation. As a results of measurements are in text presented data provided by EXFO Electro-Optical Engineering Inc. Company. Significant part of the thesis focuses on optical link Bit Error Rate (BER) which is connected with Signal to Noise Ratio (SNR) and signal quality (Q-factor). Further on it is possible to find in text about so called eye diagram which is display mode that shows influence of communication channel on shape of the transmitted signal. To this diagram is related another one called constellation diagram which describes modulation mode and makes it possible to map dispersion of signal points around their nominal values. In connection with so called trajectory it makes vector diagram. Practical part includes depiction of these diagrams in MATLAB development environment.
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Design of Graphic Interface for Calculation of Differential Group Delay
Vohralík, Jan ; Křivánek, Vítězslav (referee) ; Kyselák, Martin (advisor)
The Bachelor's thesis is aimed to the problems regarding Polarization mode dispersion in optical fibre. Polarization mode disperzion limits the bandwidth of high speed comunication system. It cases a differential group delay between different polarizatins. If the delay is too high than the bits overlap and a bit error rate is increased. The work include description of polarization in Jones space and Stokem space. For description of Polarization mode disperzion is used PMD vector. I demonstrate influence of differential group delay in optical fibre at special grafic program develop in C# language.
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Quantum key distribution test polygon
Širjov, Jakub ; Horváth, Tomáš (referee) ; Látal, Michal (advisor)
The aim of this masters thesis is to explain quantum key distribution (QKD) and principle of signal transmission in the quantum channel. Further this thesis complains commercial distributors of QKD technologies and their individual appliances. Practical part of the thesis is separated to 3 parts. First part handles transmission of quantum keys in QKDNetsim simulator. Second part takes care of design and creation of a test polygon that allows for testing of many optical network configurations with quantum signal and normal data traffic being transmitted in a single fiber. Multiple simulations of use of various filter types to supress the signal noise in the program VPIphotonics and tested by QKDNetsim are shown in the last part of this thesis.
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Technology of monofilamentous fibers based on oxidized hyaluronic acid
Běťák, Jiří ; Mráček, Aleš (referee) ; Burgert, Ladislav (referee) ; Klučáková, Martina (advisor)
Předkládaná dizertační práce se zabývá vývojem technologie výroby nového typu biodegradabilních vláken na bázi oxidované kyseliny hyaluronové. V rámci práce je postupně představován vývoj jednotlivých jednotkových operací výroby, jejichž správné porozumění a schopnost jejich řízení jsou klíčové pro žádaný chod celé vícestupňové technologie. V rámci práce je představen nezbytný vývoj technologického zařízení, průběžně konstruovaného pro účely laboratorního testování a následně až po samotnou linku pro finální výrobu vláken, která byla realizována v roce 2015. V rámci dizertační práce jsou dále navrhovány možnosti dodatečné chemické úpravy vláken s ohledem na zvyšování jejich stability ve vlhkém prostředí. S ohledem na cílené aplikace vláken pro vnitřní chirurgické implantace, jsou v práci vlákna též hodnocena z hlediska jejich materiálové biokomaptibility (toxicity).
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Design of Multiplex Optical Fibre Link
Krejča, Libor ; Křivánek, Vítězslav (referee) ; Kyselák, Martin (advisor)
In this thesis I consider problems of optical multiplexers, optical amplifiers and designing optical networks with this components. CWDM and DWDM are the most common used multiplexers today. I describe principles of realization multiplexers from basic level to realization in WDM networks. EDFA is also common used amplifier today and I describe his internal structure and how it works. Today, we can observe many realization of optical netwoks with Raman amplifiers, especially in long haul networks. Raman amplifier is characterized in brief. In next chapter I describe the design of optical communication systems and the main designing equations are explained. Then I used the equations for example of designing optical communication system with multiplexers, EDFAs and other components, which are needed for function of the system. In last chapter I explain mathematical model of signal propagation in optical fiber called nonlinear Schrodinger equation, which includes main optical effects in fiber like chromatic dispersion or Kerr effect. The simulation model and his numeric solution was designed including PMD effect, the simulation model is programmed in MATLAB.
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Studying the properties of fiber cement composites
Cederová, Kristýna ; Hoško, Marek (referee) ; Bodnárová, Lenka (advisor)
This diploma thesis deals with fiber-cement composites. Input materials are investigated for the production of fiber cement, are examined, the production and parameters of the pulp were monitored. Further, Hatschek's production technology and requirements for corrugated fiber-cement roofing are described. In the practical part the individual input materials and parameters of ground pulp were verified. The problem with production of samples and difference in the fineness of pulp milling in fiber cement products has been solved.
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