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CDMA Network Capacity
Pasečný, Jan ; Kejík, Petr (referee) ; Hanus, Stanislav (advisor)
The Bachelor thesis deals with determining which factors influence the capacity of CDMA network. This type of network is now being used worldwide due to its huge increase in capacity when compared to other transmissions systems. The work contains summary of basic parameters of single-cell and multi-cell systems with reference to the capacity. Obtained results are assesed and compared at the end of the work.
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Quality and accessability measurement of GSM network
Vondra, Marek ; Wieser,, Vladimír (referee) ; Hanus, Stanislav (advisor)
The thesis is specialized on a possibility of measuring qualities and availability of a cellular radio system and also on evaluation qualities, fruitfulness interface, permeability etc. It includes short description of a basic mobile technology. Further analysis of the possibility of measuring the mobile network and how implement the measure. It also includes a draft program for measuring and evaluation of the GSM network with help several tests by a mobile phone connected through the Bluetooth.
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Femto cells in next generation mobile networks
Bernkopf, Jan ; Štencel, Vít (referee) ; Hanus, Stanislav (advisor)
This paper provides theoretical analysis of LTE network and Femto cells. Its presents their modulation and transition techniques, their performance and of course implementation of Femto cells into LTE macro-layer. It also describes potential risk of interference between LTE macro-layer and Femto cells and provides the way how to solve and simulate interference. Finally it states simulation and analysis of model situations.
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Channel estimation in CDMA systems
Kadlec, Petr ; Prokopec, Jan (referee) ; Kejík, Petr (advisor)
The subject of this work deals with the problem of channel estimation for CDMA systems. This method of multiple access when individual users share the same full bandwidth simultaneously and are differentiated with any of pseudorandom sequences, is now the most perspective method. That is proved by its wide implementation in mobile networks of the third generation and higher systems. This work describes basic theory principles of spread spectrum, above all DS-CDMA (Direct Sequence-CDMA) and furthermore some phenomena of radio wireless channel that affect changes in transmitted signal in its way from transmitter to receiver. Terms of fading, multipath propagation, loss, refraction, scattering of the wave and Rice and Rayleigh probability density functions are mentioned. The third chapter deals with yet known and used capabilities of channel estimation. Differences, advantages and disadvantages of so-called blind estimation or training-based estimation are discussed. Two algorithms: LS method and sliding correlator are analyzed in more detail. There is also description of their simulations in Matlab and some results of these simulations are discussed. The last chapter deals with comparison of main characteristics and achievable accuracy of wireless channel impulse response estimation by both methods, and their possible utilization in real live.
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Model of UMTS System
Srdínko, Milan ; Gleissner, Filip (referee) ; Hanus, Stanislav (advisor)
Spread Spectrum Communication techniques have been widely used in mobile and wireless communications. They have very beneficial features like antijam and security (noise-like character, pseudorandom codes usage). At first, the features of Spread Spectrum systems are described with emphasis on the Direct Sequence Spread Spectrum (DS-SS) scheme. Main specifications of UMTS system are also introduced. The goal of this thesis was to create the model of a physical layer UMTS suitable for investigation of disturbing signals influences in Matlab Simulink. This model was used to measure how the Bit error rate (BER) is affected by the Processing gain and the Signal-to-noise ratio. Finally, two important charts which describe the relation of Bit error rate versus the Processing gain and the Signal-to-noise ratio have been plotted.
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Notes to multistage Wiener filter in DS-CDMA detector
Šimša, Jan
The contribution follows report oriented towards design of Wiener filter in DS-CDMA detector of signals as a multistage structure. Such approach avoids evaluation of the inverse of a known autocorrelation matrix of a sampled response of the chip matched filter to a wide-sense stationary input signal. The contribution gives more detailed description of detector signal processing and its consequences.
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Mobile internet in the Czech republic and abroad
Výborný, Vojtěch ; Žamberský, Martin (advisor) ; Bruckner, Tomáš (referee)
This bachelor deals with the mobile Internet in the Czech republic and world-wide. In the first part the development of the mobile Internet in the Czech republic from the beginning up till the current situation is addressed. The following part focuses on the analysis of the Czech providers' market and on respective technologies employed. In connection with this part the biggest providers of the mobile Internet in the USA are being analyzed. The next part outlines the anticipated development of mobile technologies. This forecast is based on analyses and own assumption. The final part consists of the analysis of markets, where T-Mobile is active.
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Mobile internet access options in the Czech Republic
Křižka, Radek ; Pour, Jan (advisor)
The topic of the presented thesis is description of mobile internet access in the Czech Republic and Slovakia. The theoretical part is focused on an individual description of the technologies, which are available in the Czech Republic, i.e. GSM, GPRS, EDGE, UMTS and HSDPA. The practical part aims at mobile network operators on the Czech and Slovak market. Each company is shortly introduced, concurrent offers and coverage are presented. Furthermore the possibilities of mobile internet access are compared one to each other. The contribution of this work is to provide a comprehensive picture of mobile internet access from the theoretical point of view, as well as from the practical.
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Internet connection for mobile users
Špírek, Martin ; Pavlíček, Luboš (advisor) ; Gála, Libor (referee)
In this work I am writing about more and more occurring phenomenon, which is opportunities to connect to the internet for mobile users. I am describing and comparing technology to serve those internet users who need to connect from different locations, or require a connection to the internet on their travels. In the first part of thesis I am explaining the most important and frequently occurring terms, which will help to better understanding and orientation in other parts of the work. The chapter "Definition of basic terms" is followed by chapter "Wireless technology connection" in which are described in greater detail the various technologies available for wireless internet connections and also the advantages and disadvantages of this connections. The second part of my work is focused more practical. There are mentioned real possibilities how to connect wireless to the internet available in the Czech Republic and they are compared with each other. There is also a comparison of mobile operators and their services, which are involved in providing internet access. I tried to also explain here what type of connection is suitable for whom. There are also given here the results of the measurements of speed and quality connection provided by mobile operators. The goal of my work is to acquaint readers with in these days very different wireless options how to connect to the internet and their basic characteristics and then comparing these technologies to facilitate the selection of potential users for the best type of connection.
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