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Analysis of parameters and communication protocols on radio interface of UMTS networks
Plhák, Jan ; Skořepa, Michal (referee) ; Novotný, Vít (advisor)
These times the third generation cellular networks are getting in use increasingly and they dramatically exceed the parameters of second generation networks. Third generation networks are in contrast to older generations data-oriented, providing better maintenance in data and multimedia services. The most widespread third generation network is the UMTS, designed as succesor of GSM network. Master’s thesis is focused on parameters and communication protocols of radio interface of UMTS network. Parameters of radio interface affect the behaviour of mobile terminal through utilization of network services. This thesis describes individual protocols of radio interface and individual procedures, which the mobile terminal have to perform through its staying in the cell. Theoretical part of this thesis considers description of the UMTS network and individual procedures and parameters. Practical part is focused on measuring the radio interface and individual procedures in real UMTS networks. Some procedures are simulated in network simulation software. This thesis includes a lab task focused on this thema.
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Design of communication network at a congress hotel
Rozlílek, Radim ; Ondrák, Viktor (referee) ; Novotný, Vít (advisor)
The bachelor's thesis deals with the complete design of a data communication infrastructure for a new congress hotel building in the vicinity of Humpolec. The starting point of the work are the requirements of the investor and project documentation. The work completely describes the procedures and resources needed for the implementation of a computer network.
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4G mobile network design issues
Žůrek, Martin ; Škorpil, Vladislav (referee) ; Novotný, Vít (advisor)
he first section briefly describes the history and development of mobile telecommunications networks, by their standards and the gradual development of global initiatives for the unification of the network. The second part of my work is focused on the latest generation cellular networks. The transition from the previous generation of networks and communication between them. Including differences in the architecture of the fourth generation. Description of the basic blocks of a new core and access networks, its use for commercial purposes.
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Mechanisms of QoS assurance in fixed, wireless and mobile data networks
Václavek, Radovan ; Novotný, Vít (referee) ; Molnár, Karol (advisor)
This bachelor´s thesis deals with mapping technologies and base parameters used to guarantee the quality of systems in the local area networks, including wireless and mobile ones. I have focused mainly on requests and classifications, which are typical for the types of networks on link layer. In Ethernet I focused on the gradual trends in the fore mentioned technologies and IEEE 802.1Q and connected IEEE 802.1p standards included. The next part describes the quality of systems in wireless nets in different types of environments and again uses given standards for quality of systems guarantee in 802.11e and connected 802.11a/b/g standards. The next part focuses on the latest generations of mobile nets, looking at the types and trends of the latest technologies. Here I draw from standard project 3GPP, which describes the problems with these technological developments. The next part focuses on WiMAX technologies. In the penultimate paragraph, the constituent network technologies are compared from the view of securing QoS and I propound possible ways of securing coversion of constituent technologies. The conclusion summarises all the technologies I have mentioned and the future trends including possible problems and challenges with these latest technologies.
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Radio Access Network of a Cellular Network
Duda, Michal ; Novotný, Vít (referee) ; Krkoš, Radko (advisor)
The aim of the work is the radio access network of mobile networks second, third and fourth generation. The main objective is a description of the radio access network of the second, third and fourth generation, their elements, interfaces and signaling procedures. The next part describes the emergency services and the architecture of the fourth generation mobile networks. The practical part is then devoted to identify actions needed to prepare radio access network to testing emergency services, identify actions needed to conversion of transport protocol fixed part of the radio access network from IPv4 to IPv6 and describe the intervention to radio access network to change the active segment of the core network.
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Optimization of UMTS access network
Havlíček, Karel ; Kovář, Petr (referee) ; Novotný, Vít (advisor)
This master’s thesis deals with a UMTS radio access network optimization, containing radio interface analysis, services and procedures description, ways to correct parameters calculations and settings and other issues necessary for a correct access network operation. The goal is effective network operation, minimum costs and maximum performance and flexibility of the network. The optimization during system operation is important because of the system character. The UMTS system uses the WCDMA technology, where particular users share the same frequency band and they are distinguished from one another via code sequences. The capacity of such a system is then given by the interference level - each particular user increases the interference level by the value corresponding to his transmit power. The maximum cell capacity is determined by the maximum interference level at which users can still operate with required services, so it is related not only to the number of users, but also to their bit rate. The optimization allows effective usage of the system for different services with different requirements. The main optimization tool is the radio resource management, containing number of algorithms, such as admission control, which decides the acceptance or rejection of a new user demanding certain service, power control, which ensure that users transmit with a minimal power sufficient for required service, handover and cell selection algorithms etc. The major parameter used by these algorithms is a cell load factor, which is related to the interference level margin. There are several methods for the load factor estimation and some of them are described in this work. Some other optimization techniques are mentioned here, too. This work also contains a laboratory exercise proposal for radio resource management introduction using the OPNET Modeler network simulation tool.
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Automatic Classification of Digital Modulations
Kubánková, Anna ; Novotný, Vít (advisor)
This dissertation thesis deals with a new method for digital modulation recognition. The history and present state of the topic is summarized in the introduction. Present methods together with their characteristic properties are described. The recognition by means of artificial neural is presented in more detail. After setting the objective of the dissertation thesis, the digital modulations that were chosen for recognition are described theoretically. The modulations FSK, MSK, BPSK, QPSK, and QAM-16 are concerned. These modulations are mostly used in modern communication systems. The method designed is based on the analysis of module and phase spectrograms of the modulated signals. Their histograms are used for the examination of the spectrogram properties. They provide information on the count of carrier frequencies in the signal, which is used for the FSK and MSK recognition, and on the count of phase states on which the BPSK, QPSK, and QAM-16 are classified. The spectrograms in that the characteristic attributes of the modulations are visible are obtained with the segment length equal to the symbol length. It was found that it is possible to correctly recognize the modulation with the known symbol length at the signal-to-noise ratio at least 0 dB. That is why it is necessary to detect the symbol length prior to the spectrogram calculation. Four methods were designed for this purpose: autocorrelation function, cepstrum analysis, wavelet transform, and LPC coefficients. These methods were algorithmized and analyzed with signals disturbed by the white Gaussian noise, phase noise and with signals passed through a multipass fading channel. The method of detection by means of cepstrum analysis proved the most suitable and reliable. Finally the new method for digital modulation recognition was verified with signals passed through a channel with properties close to the real one.
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QoS in IP network
Bumbál, Miroslav ; Novotný, Vít (referee) ; Růčka, Lukáš (advisor)
Master 's thesis deals about computer networks, which constitutes a global communication structure and play a very important role in today's society. The rapid development of Internet, the emergence of new multimedia applications and their increasing use of calls to the efficient functioning of the creation of such governance mechanisms of transmission, which are able to secure the required parameters. The thesis deals about the issue of quality of service (QoS) in IP networks. It presents the basic characteristics and requirements of these networks for the transmission of sensitive data by the quality of services, deals with the QoS definition, and describes the essential parameters to be followed to achieve the required quality of service in practical deployment. In addition, lists the various principles and options to ensure QoS in computer networks. Generally, it represents the Cisco 1841 router features and options to ensure quality of service in the network based on these routers. Practical thesis part provides two types of model IP networks, which were designed in order to verify the impact of service quality in real practice. Of the known methods to ensure QoS, which include a mechanism of Integrated services, Differentiated services, it focus its content about the Differentiated Services and the implementation of these in proposed network model. The last part of the work presents the results obtained by the impact of quality of service for the applications and their assessment.
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Routing among autonomous systems in Internet
Daněk, Michal ; Komosný, Dan (referee) ; Novotný, Vít (advisor)
Bachelor thesis describes the architecture of the Internet, its division into autonomous system and methods of their interconnection. Furthermore extensively describes routing mechanisms among autonomous system but also inside. More space is dedicated to routing protocols OSPF and BGP. At the end of the work is designed laboratory task for subject Network Architecture where this protocols are used.
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