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Free-Space Optics data link
Šála, Jakub ; Číž, Radim (referee) ; Šporik, Jan (advisor)
In this thesis, shows a current issue for free space optics, limiting their use in practice with regard to the availability and reliability. They conducted measurements on wireless optical links and the observed values is calculated by the availability of the connection. Subsequently, measurements are performed on alternate versions of wireless and copper connections. Observed values were compared with a wireless optical link. It is made of optical design of wireless connections at home.
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Design and management of WDM systems for optical networks
Červenka, Vladimír ; Šporik, Jan (referee) ; Tejkal, Vladimír (advisor)
This thesis describes single types of wavelength-division multiplex (WDM) according to the International Telecommunication Union (ITU-T). This work offers an overview of components and evaluation of critical parts of network design utilizing WDM technology. There are depicted typical properties, suitable components and channel spacing for each category. Suitable optic fibers according to ITU-T and characteristics of negative effects can be found in the work as well. Furthermore, there are presented most important optic sources, optic amplifiers, optic detectors with filters their requirements and application. They are especially important for achieving operation of WDM system. The fifth chapter considers impact of negative effects in fiber optics and their influence on the system. Then, a WDM system is designed along with management and monitoring the physical layer. The work also presents 1,33 Tbit/s (32 × 42,7 Gbit/s) WDM transmission over 300 km (with three 100 km spans) of post-compensated non-zero dispersion-shifted fiber (NZDSF) LEAF. The capacity of 400 Tbit/s×km is achieved in a single 25,6 nm C band using non-return-to-zero differential phase-shift-keyed modulation (NRZ-DQPSK), balanced detection and erbium-doped fiber amplification. Together with design of transmission system a several simulative analysis has been carried out in order to find the optimum configuration (such as number and distances between amplifiers, length of spans or the way of dispersion compensation) for a high bit rate optical transmission system. It was used a program OptiSystem 8.0.
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Wireless connections for metropolitan networks
Svoboda, Jan ; Tejkal, Vladimír (referee) ; Šporik, Jan (advisor)
This Master’s thesis analizes technologies suitable for metropolitan area networks. In this thesis there are mentioned technologies used for wireless transfer with speeds above 1 Gbps. There are described basic features and parameters of microwave radio relay links in 70/80GHz range and free space optic links. These technologies are compared with classic optical networks. Practical part of thesis was focused on development of application which calculates signal attenuation caused by the passage of the atmosphere for both technologies. Results gained from this application are mentioned in this Master’s thesis.
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Mathematical analysis and simulation of optical fiber transmission parameters
Smrž, Jan ; Šporik, Jan (referee) ; Tejkal, Vladimír (advisor)
This thesis deals with the transmission of optical fibers, their properties and method of calculation. The paper presents different types of fiber types and standards. There is a description of the connection of optical fibers with different methods, including variations joints. Further side effects are broken fibers, dispersion and attenuation. The last part is devoted to describing the program, which was part of this work. The program is used to calculate the transmission parameters of optical fibers and optical losses incurred in connection.
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Optical connections and their influence on transmission
Jaroš, Pavel ; Šporik, Jan (referee) ; Tejkal, Vladimír (advisor)
The aim of this bachelor‘s thesis is to evaluate the current options of connecting optical fibres and their application in specific situations. Firstly, I will deal with fiber optic system and its components in detail. Then, this topic will be futher developed by discussing fibre connection problems, fusion splicing for making permanent fiber join, mechanical splice and, most of all, optical connectors. In following chapters I introduce mathematical dependence of attenuation on the relative possition of the ends of fibers. Another aim of the work was to create an application in a suitable programming enviroment, which will be used for design of optical path.
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Optical amplifiers for metropolitan and access networks
Čech, Martin ; Šporik, Jan (referee) ; Tejkal, Vladimír (advisor)
Aim of this Master´s thesis is to describe and compare most common types of optical amplifiers used in today’s networks. The first section focuses on problematic of optical transmissions and phenomenon which cause degradation of transmitted signal. It is also explained in this section why there is a need to deploy optical amplifiers. Next section describes basic principles, structure and properties of individual types of optical amplifiers. Following section describes simulations which were made to compare the performance of transmission systems with each individual type of optical amplifier. The last section contains a design of optical metropolitan network with wavelength multiplex. Based on simulations from preceding part best amplifier type and optimal amplifier placement was selected. Functionality of the design was tested and simulations described in final section.
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Optimization of access networks for multimedia services
Slavíček, Tomáš ; Reichert, Pavel (referee) ; Šporik, Jan (advisor)
This thesis describes the problems of access networks and their existing types. It discusses the important parameters for multimedia services. It considers the possibility of using various networks at the localities. It presents modern multimedia services and their requirements for access networks. Next step describes the possible use of QoS to optimize access networks used for multimedia services. Multimedia services to different types of networks and limits which these types of networks have, are simulated in the program Opnet Modeler. Measurements of values important for securing quality of services are implemented at selected real access networks. In conclusion, the results of simulations and measurements are subjected to comparative analysis.
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Plastic optical fibres and their application in practice
Bubela, Ondřej ; Tejkal, Vladimír (referee) ; Šporik, Jan (advisor)
The intention of this essay is familiarize readers with polymer optical fibers knowed as POF. Listing the losses factors (attenuation, dispersion) and transmition properties (bandwidth, index profiles). Describes production POF (suitable materials and methods), connecting with detachable and not detachable joints. Discuss and compares diference between GOF and POF. By measuring demostrates the complexity of compilation POF and GOF physical layers. Define the facts affecting transmission parameters. Trying to inform about economical possibilities.
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Advanced system for computer data back-up
Sobek, Jiří ; Šporik, Jan (referee) ; Vychodil, Petr (advisor)
This master thesis is mainly focused on the backup systems and describes each individual backup techniques in detail. Next main point of this thesis, is explaining functionality of IPv4 and FTP, which are closely related to the topic. Outcome is a backup application written in Java language, which is capable of backup files on FTP server or on local/ network storage area. Backup application also allows settings for automatic backup and restoring files from the storage area. Finally there was made a measurment, where were point out advantages and disadvantages of transfer mediums and where was practically shown a logic of creating the backup system. Goal was a creation of multiplatform backup application.
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Photonic crystal fibers
Dočkal, Martin ; Tejkal, Vladimír (referee) ; Šporik, Jan (advisor)
This graduation thesis deals with use of unconventional optical fiber with the intention of photonic crystal fiber. There are described types of photonic crystal fiber, their physical, optical and transfer characteristics. There is explained what are the photonic crystals, principle of their function and possible types of crystals. There are also detailed types of photonic fiber commonly used in the optical fiber branch. There is also explained photonic crystal fiber its structure a hierarchy of its types. In this thesis are described and demonstrated different kinds of photonic optical fiber and their use. There is demonstrated principle of one-dimensional periodical structure of Bragg fiber using simulation software. There can be seen graphical comparison of the simulated optical fiber core to commonly obtainable fiber. Outcome of this graduation thesis should be explanation of function of photonic crystal fiber and possibility of finding new type of fiber with optimal dispersion characteristics for use in fiber optics.
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