National Repository of Grey Literature 204 records found  beginprevious195 - 204  jump to record: Search took 0.01 seconds. 
Parameters of FTTx networks - Quality of services
Winkler, Aleš ; Reichert, Pavel (referee) ; Münster, Petr (advisor)
The main subject of this diploma thesis is to make a proposal to improve the optical access network for the transmission of Triple play services. I would here to the reader clarify method of proposal of optical network. There are described the kinds of optical access networks with parameters, for which we must look by their construction. There are described the modern methods of construction optical network too. In the theoretical part are discussed used architecture of networks too. I met here known standards, which I compared for big importance by their choice. A reason of construction of optical network are services known like Triple play. These services together with their problems and parameters are here discussed too. At the end of theoretical part I listed here measuring method for getting negative attribute distorting the led signal. In practical part the locality witch use the optical signal as the source of information is ordered. These network use unfit connections and has less possibilities than usual and this is the reason, why is the network not able to supply Triple play in requested quality. At first the analysis of ordered network was needed. Situation was complicated by the fact, that it has been prohibited entrance to me. The structure of network and network parts was known and documented by me. I made the proposals to improve this network in practical part. By the first proposal remained original kind of access network FTTB, but used new parts with higher performance. By the second proposal I made the network FTTH, by which it was possible to use the last haul optical cables with treatment and using new elements. It was needed to create solution by flat units. The resulting proposals are here evaluated, compared and cost evaluated. For rejection of access to optical network I did not make measuring, so I made simulation for variant FTTH for getting some parameters negative acting transmission.
Parameters of FTTx networks - Quality of services
Winkler, Aleš ; Reichert, Pavel (referee) ; Münster, Petr (advisor)
The main subject of this diploma thesis is to make a proposal to improve the optical access network for the transmission of Triple play services. I would here to the reader clarify method of proposal of optical network. There are described the kinds of optical access networks with parameters, for which we must look by their construction. There are described the modern methods of construction optical network too. In the theoretical part are discussed used architecture of networks too. I met here known standards, which I compared for big importance by their choice. A reason of construction of optical network are services known like Triple play. These services together with their problems and parameters are here discussed too. At the end of theoretical part I listed here measuring method for getting negative attribute distorting the led signal. In practical part the locality witch use the optical signal as the source of information is ordered. These network use unfit connections and has less possibilities than usual and this is the reason, why is the network not able to supply Triple play in requested quality. At first the analysis of ordered network was needed. Situation was complicated by the fact, that it has been prohibited entrance to me. The structure of network and network parts was known and documented by me. I made the proposals to improve this network in practical part. By the first proposal remained original kind of access network FTTB, but used new parts with higher performance. By the second proposal I made the network FTTH, by which it was possible to use the last haul optical cables with treatment and using new elements. It was needed to create solution by flat units. The resulting proposals are here evaluated, compared and cost evaluated. For rejection of access to optical network I did not make measuring, so I made simulation for variant FTTH for getting some parameters negative acting transmission.
Design of Passive Optical Network
Asensi Pla, Juan Salvador ; Reichert, Pavel (advisor)
El constante incremento en la demanda de servicios de banda ancha y el consecuente aumento del volumen de tráfico que se genera en nuestras redes de comunicaciones, han motivado la necesidad de implementar redes de nueva generación en nuestros territorios. El presente proyecto final de carrera tiene como objetivo explicar el diseno y la planificación de una red pasiva de fibra óptica (PON). La idea principal de este proyecto es construir un entorno ficticio que nos permitirá profundizar en detalle en las redes FTTx y decidir cuál es la opción más optima para este entorno. Para hacer esto posible, en primer lugar se va a hablar sobre el elemento principal de estas redes, la fibra óptica, para conocer con detalle sus principios de funcionamiento y sus características más importantes. La parte teórica seguirá con la definición de las redes FTTx y las configuraciones punto a punto y punto a multipunto, para pasar a hablar detenidamente sobre las redes PON y concluir cual de sus tecnologías será la más optima hoy en día. Por último, entraremos en la parte práctica en la que se elegirá un software de simulación que se ajuste a los requisitos de diseno, se realizará el diseno de la red óptica pasiva y se obtendrán los resultados de simulación que justifiquen que la red es viable y puede ser implementada en un caso real.
Optical fibres and their polarization effect
Klesnil, Ondřej ; Dostál, Otto (referee) ; Filka, Miloslav (advisor)
This project describes the fundamental concepts and basic theory of polarization mode dispersion (PMD) in optical fibers. There are described basic the relation between Jones vectors and Stokes vectors, rotation matrices, the definition and representation of PMD vectors, the laws of infinitesimal rotation. After the introduction the first conception with bases of polarization mode dispersion (PMD) in optical fibers, they have become an important body of knowledge basic for the design of high-capacity optical communication systems. PMD effects are linear electromagnetic propagation phenomena occurring in so-called “single-mode“fibers. Despite their name, these fibers support two modes of propagation distinguished by their polarization. Because of optical birefringence in the fiber, the two modes travel with different group velocities, and the random change of this birefringence along the fiber length results in random coupling between the modes. With current practical transmission technology the resulting PMD phenomena lead to pulse distortion and system impairments that limit the transmission capacity of the fiber. I describe different ways of measuring PMD in optical fibre, PMD compensation techniques and analyse PMD results in optical fibres.
"Triple Pley" - FTTH
Bobkovič, Peter ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
This project is zaobíra possible implementation of the last mile connection to užívateli through FTTH, what is optics to the home. The whole work is divided into 2 parts, and to a general overview of FTTH and its own measurements. In general overview of the listed species gradually FTTH networks, problems associated with FTTH, zmapovaná situation in the world and Triple game (Pricelist, ponuka TV and under.). In the second part of the developed progressive measure, and the results of the three carried out measurements (PPM, OTDR, directly method) as well as the appearance of purity connector.
Wide-band FTTx Networks Terminal in WDM - PON architecture
Bobkovič, Peter ; Reichert, Pavel (referee) ; Filka, Miloslav (advisor)
This masters thesis is focusing on the issue of passive optic access networks. It is dealing with the limiting factors for broadband connections, especially attenuation of fibre optics and dispersion. It is also dealing with most commonly used standards of passive optic networks. It clarifies the issue of wavelength-division multiplexing, its advantages and disadvantages, used standards, various types of components for the WDM-networks, their characteristics, application etc. In the practical part of the work you can find the measuring and diagnostics of the passive optic network EPON. It contains measuring by the direct method OLTS, measuring by the Pon Power Meter and optic reflectometer OTDR. At the end I am dealing with the measuring of splitter in the rate of 1:16.
Multimedia networks in cars
Knopp, Petr ; Krajsa, Ondřej (referee) ; Koutný, Martin (advisor)
Moderní elektronika se stává nezbytnou součástí dnešních automobilů. Dynamicky se rozvíjející informační a telematické služby nacházejí široké uplatnění v automobilovém prostředí. Moderní aplikace vyžadují přenos velkého množství dat, což jim zajišťují dnešní komunikační protokoly. Cílem mé diplomové práce je analýza a návrh implementace multimediálních sítí do automobilů. Jednotlivé návrhy jsou charakterizovány a srovnány podle požadavků, kterým jsou v automobilovém prostředí vystaveny. Navržené topologie využívají nejen dnes používané technologie, ale jsou zde i návrhy, které nebyly dosud v automobilovém prostředí použity. Jednotlivé návrhy jsou srovnány a vyhodnoceny z pohledu automobilového výrobce.
Effects of mechanical doings on optical data transport
Tihlařík, Tomáš ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
This master´s thesis deals with of human factor impact on optical fibers manipulation. It describes types and methods used for splicing and placing optical fibers and optical cables. These methods are specified in the chapters; their application in different environments and conditions is accentuated. This paper presents splicing optical fibers. It emphasizes problems which can occur if proper procedures aren´t kept or if improper device is used. In the thesis there is the chapter dealing with problems which can arise during splicing optical fibers - these negative influences are evaluated with educational equipments EF-970-01 PLASTIC by the company MIKROKOM, s.r.o. Another aim of the work is to describe mechanical optical fiber splice 3MTM FibrlokTM. This kind of device was lent for testing optical fibers multiple splicing. It was tested under extreme conditions. Statistically processed values of insertion loss and splice reflectance, measured by OTDR are the results of the test. Comparing measured values, technical report ones, regarding for usage in practice, there is a possibility of 75 multiple reusing of the mechanical optical fiber splice. The prediction of magnitude insertion loss, calculated for thousands splice cycles follows. The next part of the work deals with fusion splices and contains comparison of splices made with two cleavers: CORNING LWL-TRENNGERAT S46999-M9-D12 and the later model - Fitel S325A cleaver. The result is that older S46999-M9-D12 model gained lower attenuation. The results of both previous measurements are influenced by human factor. It appears at mechanical optical fiber splices as growing fluctuate of insertion losses and as the unequal attenuation fusion splices at tested cleavers.
SNOM probes with special properties
Slabý, Vít ; Kalousek, Radek (referee) ; Spousta, Jiří (advisor)
This bachelor thesis deals with scanning near-field optical microscopy. With SNOM we examined experimentally the near field of the interference of surface plasmon polaritons (PPP) on plasmonic structures consisting of slits in a metal layer a we discuss the effect of probe characteristics on the measurement results.Effect of few characteristics is simulated numerically. Findings obtained in the previous experiments are used for the construction designing of an experimental device called NanoGIS, which should serve for the nanostructure manufacturing.
Literature Retrieval of Robotic Griping System Force Control
Fousek, Jan ; Vlach, Radek (referee) ; Krejčí, Petr (advisor)
The aim of this work is making research on the measurement and control of downforce of robotic members. Much of the work is focused on an overview of the sensors for sensing the applied force. The second part deals with the design for fingertip sensor robotic hand.

National Repository of Grey Literature : 204 records found   beginprevious195 - 204  jump to record:
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