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The combined structures in optical fiber
Klvaňa, Jakub ; Čučka, Milan (referee) ; Urban, František (advisor)
The aim of this master’s thesis is familiar with the problems of optical fibers and possi- bilities creating functional optical structures in optical fibers. first section focuses on the optical fibers and their properties. Another chapter deals with the functional structures of optical fiber and their production. Next section is devoted to the analysis of combinations of these functional structures and their potential applications in sensors. Subsequently, a combined structure is proposed, which is later produced, measured and evaluated for possible use in the sensors
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Longitudinal index structures in optical fibers
Polreich, Štěpán ; Čučka, Milan (referee) ; Urban, František (advisor)
This thesis describes basic concepts, principles and properties of optical fibers. Considerable part is devoted to fiber gratings that are created by a change in the refractive index in the optical fiber core. In this work is described description, principle, method od production and distribution of gratings on Bragg gratings, gratings with long period and chirped gratings. In this thesis are also presented different types of lasers and their advantages over other lasers. A large part deals with the description of the femtosecond laser, with which the structures will be later made into the material. In addition, the laser modes are differentiated, this is a mode of micro-machining and modification or a change in refractive index of the material. The last part deals with change the refractive index in planar technology, the creation of a groove for fastening the fiber and attempts to write the gratings into the optical fiber. Created fiber sensor are tested for temperature and tensile changes. Finally, the practical use of sensors made by femtosecond laser and the advantages over UV laser and phase mask techniques are presented.
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Distributed fiber optic sensors
Holík, Tomáš ; Čučka, Milan (referee) ; Münster, Petr (advisor)
The thesis deals with the possibility of using optical fiber as a sensor. The introduction of the thesis is devoted to the foundations of optics. In addition, the thesis deals with optical interferometry, polarization and dispersion in optical fiber. The main output of the thesis is the comparison of acoustic vibration measurements using interferometric and polarization methods and further measurements on the real route in Brno.
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Optical Distributed Sensor Systems
Dorazin, David ; Münster, Petr (referee) ; Čučka, Milan (advisor)
This bachelors thesis solves possibilities of utilization optical fiber as a sensor. At the beginning the thesis desribes basic principle of ligh transmition in optical fiber, optical fiber and his linear and nonlinear properties. Second part of the thesis deals with sorting of distributed optical fiber sensors and describes each type of the sorted sensor due to principle which they work on. The Michelson interferometer is described and its modification in the form of the Fiber optic Michelson interferometer, which is designed and simulated in the VPIphotonics software. At the end of the thesis is performed measuring of vibrations by the Fiber optic Mach-Zehnder interferometer.
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Verification of stable next generation networks via transmission parameters measurement
Gregor, Lukáš ; Čučka, Milan (referee) ; Grenar, David (advisor)
This thesis deals with the measurement of transmission parameters in the new generation access networks NGA. The aim of the thesis is to build and configure a test network and scenarios for the measurement of service quality parameters and then verify the transmission stability. The theoretical part describes general functioning of NGN networks, the requirements of different telecommunications services on quality parameters, methodology and recommendations for measuring transmission parameters in packet networks. The practical part deals with the configuration of scenarios using mainly MPLS technology and methodology of their testing. Measurements were performed according to recommendations IETF RFC 2544, IETF RFC 6349 with the ExacTCP test and ITU-T Y.1564 with the EtherSAM test. For measurements were used measuring instruments of EXFO brand. In conclusion, the measurement results according to the mentioned standards were evaluated and also the advantages of using the measurement according to the given standard in NGA access networks were discussed.
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Measurement of polarized lightparametrs measurement on the optical-fiber sensor output
Drábek, Jakub ; Čučka, Milan (referee) ; Filka, Miloslav (advisor)
This master's thesis deals with the analysis of the optical power measurement using an optical fiber sensor. The thesis contains the theoretical background to understand the origin of polarization and its representation in space using Poincaré’s sphere and Stokes vectors. There is also a part describing optical performance measurement and the preview of analog measurements from various researches. Practical part focuses on verification of changes of fiber sensor parameters at temperature change in its surroundings and this part includes also additional suggestions for various types of measurements and verification of the function of the photodiode as an optical power transducer. Most measurements are based on the comparison of results obtained with the polarimeter. The results were plotted and discussed.
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Location of vibration around the optical fiber
Dorazin, David ; Urban, František (referee) ; Čučka, Milan (advisor)
This diploma thesis solves possibilities of utilization optical fiber as sensor. At the beginning, basic division of this sensors is desribed, their principles and usage. Then the thesis is focused on distributed sensors based on the interference of the light, interferometers. This optic fiber interferometers are described, mainly their modifications for detection and localization of vibrations along optical fiber. Significant part of the thesis deals with dual Mach--Zehnder interferometer. This interferometer is theoreticaly desribed and simulated in Matlab. Further the thesis deals with development of two aplication in Matlab software. One application is for simulation and theoretical computation of dual Mach--Zehnder interferometer. Second application serves for signal processing of acquired data that are measured on this interferometer. At the end of the thesis, dual Mach--Zehnder interferometer is designed and build in laboratory enviroment and executed measurement and localization of vibrations using this interferometer.
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Search storage of fiber optic cables
Čučka, Milan ; Dostál, Otto (referee) ; Filka, Miloslav (advisor)
This work deals with the possibilities of laying and reverse lookup optical routes with the help of modern technology. Hereinafter, there are possibilities for documentation and registration of fiber optic lines. Speaking of thesis, it focuses on optical technology, advantages and disadvantages of this technology. Introduction focuses on fiber optic cable and related theoretical knowledge. Additionally, there are introduced comparisons with metallic lines. Another part is based on different searching methods for optical cables using metallic elements are analyzed in a detail. This section discusses galvanic and inductive methods. Subsequently, the thesis deals with searching for optical paths with the help of EMS (electronic marker system). Moreover, there are described individual types of electronic tags which are used in the installation of different kinds of lines. There are also briefly described seeker EMS markers, made by Dynatel. In addition to my work you can find the description of GPS (Global Positioning System) technology and routing the cable with the help of GPS system. Finally, possibility of documentation and evidence in the ArcGIS from ERSI and in the SPIDER-fiber from Gisoft is given. The overall functions of individual programs and their options are analyzed. The last section presents the implementation of laboratory tasks and programming burial markers, creating navigation in Urwigo and realisation with Openwing in Nokia phone. In the end of the work is map with markers positions.
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Simulation And Measurement Of Mach-Zehnder Interferometer
Cucka, Milan ; Salik, Pavol
The paper focuses on simulation and measurement of Mach-Zehnder interferometer. This type of sensor is used as a distributed fiber optic sensor for sensing vibration, mechanical tension and temperature. Fiber optic sensors based on optical interferometry are now widely used, e.g. Sagnac interferometer in optic gyroscopes. Mach-Zehnder interferometer is used for measurement of transformers temperature. The article includes a simulation of interferometric systems in VPIphotonics simulation software and it also includes scientific notation of a signal and a short description of the used simulation systems.
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