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Techniques solving the fiber optic dispersion on current optical links
Prášil, Jiří ; Pfeifer, Václav (referee) ; Reichert, Pavel (advisor)
This diploma thesis deals with analysis of current diagnostic methods of optical networks, and it is focused on optical fiber dispersion in singlemode fibers. The work starts with a describtion chromatic dispersion and polarization mode dispersion, causes of and thein influence on the transmitted signal at the beginning. There are set out principles and their appropriate use in the list of measuring methods. Furthermore, the work are given the current possibilities for compensation above dispersions. The sixth chapter deals with the measurements and simulations of real routes in the OptiSystem. There are given appropriate compensation methods for the selected route speeds in the last chapter. The simulation is performed for the bit rate 2.5 Gbit / s, 10 Gbit / s and 40 Gbit / s.
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Reproducibility and accuracy of polarization mode dispersion measurements
Kováč, Filip ; Brouček,, Jan (referee) ; Šifta, Radim (advisor)
Thesis is divided into two parts. The first part is written rather in theoretical way. It deals with general formation of the dispersion mathematically and verbally. It focuses on the chromatic and polarization mode dispersion. Different types of optical fibers for category G.65X are mentioned as well in connection with the ITU-T. Further attention is drawn first to compensation and then the measurement both of the mentioned dispersions. The thesis describes also analyzers and their main features. The second part is devoted to practical measurements of polarization mode dispersion. In the beginning there are described the components used for construction of the optical measurements and topologies. It is followed by an analysis of an each optical link. The results of these measurement methods and their mutual comparisons are at the end of this section. Measurements in temperature chamber is the subject of a further practical part, which from the beginning captures the essential features of the temperature chamber. This is followed by a description of the measurements, analyses and final valuation depending on the amount of polarization mode dispersion versus the temperature.
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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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Temperature Dependence of PMD
Drábek, Jakub ; Hanák, Pavel (referee) ; Münster, Petr (advisor)
Bacherol thesis describes the problems of polarization mode dispersion-PMD. Size of the delay PMD is a random variable that varies in time. When operating at high data rate communication links is one of the major problem of the optical fiber. PMD value affects many different environmental influences as temperature, and therefore the measurement of PMD become standard in deploying high-speed optical networks.
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Use of optical fiber as a temperature sensor
Procházka, Jakub ; Škorpil, Vladislav (referee) ; Filka, Miloslav (advisor)
This diploma thesis is focused on use of polarization mode dispersion for measurement of temperature. It also deals with representation of polarization mode dispersion in Poincaré sphere and a mathematical description of polarization mode dispersion by using Stokes and Jones vectors. Here are described basic alternatives of settings, selected temperature relationships and dependence and relationship between coherency and polarization. The practical portion of the diploma thesis examines behavior of the temperature sensor at different temperatures for wavelength 1550 nm and 633 nm.
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The Optical Fibre Dispersion Effects on Multiplex Transmission Systems
Kyselák, Martin ; Filka, Miloslav (advisor)
This doctoral thesis deals with present trend to turn up the bit rate of the optical fibres making use of wavelenght multiplex systems. There are new theoretical and practical problems caused by the new technologies. Except the known modal dispersion there exist problems caused by chromatical and polarization mode dispersion. In the opening of the thesis the known effects, which influence the payload signal, are introduced. The polarization mode dispersion has the main attention. Within the scope of this thesis there has been programmed the statistical calculator which can analyses the measured values of differential group delay by Monte Carlo calculation. Next meaningful output is the designating application of the optical routes. It is possible to mathematicaly unambiguously define the polarization mode dispersion by Jones, Stokes and Poynting vectors. This complicated calculations are mechanized and in the simulation application make possible to simulate the signification of the PMD influence at different input parameters. The thesis includes the study of the PMD modulation format impact with the results of simulations and confrontation with other scientists results. The significant output are the final practical results examinations, which can be implemented thanks to the possibility of using the FTB-5500B measuring device.
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Dispersion effects in high-speed optical networks
Filip, Tomáš ; Šporik, Jan (referee) ; Tejkal, Vladimír (advisor)
This bachelor’s thesis is focusing on optical transmission principal, its transfer mediums and furthermore also with focusing on its advantages and disadvantages. First half of this thesis focuses on adverse influences, which affect signal transmission in optical networks, on dispersion influences, especially on Polarization Mode Dispersion (PMD). Second half of this thesis deals with measuring of properties of optical fibers, largely chromatic and polarization mode dispersion, used methods and its principals. Furthermore, there are mentioned current compensation possibilities. The seventh chapter deals with optical route simulation in OptiSystem and testing chosen compensation methods for bit rate 40Gb/s. In the last chapter there are elaborated results of real optical route measurements for Masaryk University.
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Measurement of the fiber optical transport links
Ambrož, Jan ; Škorpil, Vladislav (referee) ; Reichert, Pavel (advisor)
This thesis deals with the measurement of optical transport links. In particular, the measurement of attenuation, chromatic and polarization mode dispersion. Specic me- asurement systems using a WDM and passive optical networks. Within each chapter are listed the causes and eects restrictive factors and methods of measurement. In chapter Attenuation measurements are described radiation and material loss as the main causes of depression. Methods whitch are described two lengths, insert loss and reectometri. Chromatic dispersion at dierent speeds of various wavelengths limits systems with high transfer rate. Methods of measuring the phase shift, dierential phase shift, pulse time delay and interference. Polarization mode dispersion is a random phenomenon caused double refraction, must be measured after completion of the route. Scanning wavelen- gth, traditional and general interference, reectometri and the polarimetric are methods of measurement. It described the measurement of WDM systems in three stages of its build. In brief PON networks are presented, with the specicities of the measurement over splitter. Most chapters are supplemented by the results and conclusions of practical measurements. At the end of the work are given by the two standards deal with the measurement of optical transport links.
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Reproducibility and accuracy of polarization mode dispersion measurements
Kováč, Filip ; Brouček,, Jan (referee) ; Šifta, Radim (advisor)
Thesis is divided into two parts. The first part is written rather in theoretical way. It deals with general formation of the dispersion mathematically and verbally. It focuses on the chromatic and polarization mode dispersion. Different types of optical fibers for category G.65X are mentioned as well in connection with the ITU-T. Further attention is drawn first to compensation and then the measurement both of the mentioned dispersions. The thesis describes also analyzers and their main features. The second part is devoted to practical measurements of polarization mode dispersion. In the beginning there are described the components used for construction of the optical measurements and topologies. It is followed by an analysis of an each optical link. The results of these measurement methods and their mutual comparisons are at the end of this section. Measurements in temperature chamber is the subject of a further practical part, which from the beginning captures the essential features of the temperature chamber. This is followed by a description of the measurements, analyses and final valuation depending on the amount of polarization mode dispersion versus the temperature.
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