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Support of service quality demands in radio access networks of high speed variants of mobile networks
Kuruc, Jiří ; Skořepa, Michal (referee) ; Novotný, Vít (advisor)
The work deals with the developmental stages (Releases) of the third generation UMTS net-works. It explains a partial improvement from Release 99 to Release 5 and Release 6 to im-prove the quality parameters of a mobile data transmission. In the practical part, there are measured qualitative parameters of the third generation networks that are available in the Czech Republic: UMTS, HSDPA, CDMA 1xEV-DO Rev.0 and Rev.A and UMTS-TDD. The measurements give reasonably achievable data rates in both directions (downlink & uplunk), a response time, quality of VoIP calls, a dispersion, a data-loss and an ability to transmit video with different data flows. The other aspects especially an availability of coverage and end-user terminals have been assessed wihin the each network. The work is supplemeted with a laboratory, which is focused on a practical comparison of the basic parameters of data transmissions of 2G and 3G networks.
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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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Special security system
Náhlík, Ondřej ; Masopust, Jiří (referee) ; Hanus, Stanislav (advisor)
This master’s thesis is focused on design and realisation of special security system for space and property protection. System is devided into two parts, transmitting and receiving. Transmitting part is formed by Raspberry Pi Model B+, motion sensor, webcam and USB LTE modem Huawei E398. Receiving part consists of computer with suitable application for communication with FTP server. Data transfer in mobile systems is described in the first part of this thesis, transmitting part is designed in the second part. There is one transmitting option chosen in the third part and there are also described applications of the transmitting part. The last part of this thesis is focused on the receiving part and its application.
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UMTS radio access network optimization in Opnet Modeler environment
Toman, Petr ; Herman, Ivo (referee) ; Novotný, Vít (advisor)
The differences between networks of mobile operators can be in their achitecture or the optimization of each network. The architecture is standardized which means there will only be differences in the willingness of mobile operators to invest in newer network elements. Network optimization is more important. The way of optimization isn't strictly given and depends on how the operator deals with it. The most important attribute in optimization is balance. The operators try to achieve balance among three important parameters. Those are capacity, coverage and maintaining QoS. Optimization depends on RRM algorithms. The algorithms include various functions such as admission control, congestion control, handover control, power control, etc. These elements don’t only affect the optimization but also affect each other, because they cooperate with each other. For example, an incorrect admission control of the network leads either to frequent network congestion because of a large number of participants in the network (participants are dissatisfied with the services offered by the operator) or to low utilization of the network because of too few participants in the network (the operator is dissatisfied because he is losing the possible earnings). Neither of these posibilities is good for the mobile operator, therefore it is important that the admission control is well balanced.
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Traffic Management in UMTS Network
Menšík, David ; Novotný, Vít (referee) ; Hošek, Jiří (advisor)
This thesis is describing UMTS network, architecture and especially maintaining Quality of Services in this network. Specifically is focused on operation control management in UMTS network. Practical part contains description of settings for UMTS network with QoS and following operational simulation. This simulation was performed in OPNET Modeler v.14.5. Others simulations were performed with different settings of QoS. Results of three simulations were compared and by that operational dependence on QoS settings was verified.
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GSM-EDGE and UMTS Systems Coexistence
Gleissner, Filip ; Hanus, Stanislav (advisor)
The dissertation thesis deals with the investigation of the coexistence of GSM–EDGE and UMTS systems with focus on the physical layer of the systems. The aim is to provide a set of recommendations for practical cooperation while the systems operate in both the separated and the common radio bands. A detailed description of signal processing of both the systems on the physical layer is presented. On the basis of this description, models of both systems were created and implemented in the MATLAB environment. The simulations are focused on the physical layer quality parameters, especially the bit error ratio evaluation for various ratios of useful signal power to noise power during the transmission over the radio channel. Simulation is also used to examine the quality of received useful signal while it is interfered by signals from the same and adjacent channels. The purpose is to determine the isolation between these adjacent channels, when the bit error ratio of the useful signal does not exceed a certain reference value. The simulation results are subsequently subjected to comparison with the results of the experimental measurements in laboratory conditions. Before the measurements are carried out, a study of possible interference types is performed. Consequently, the crucial parameters of the measuring equipment used are verified. From the results of simulations and measurements, the proposal of a minimum and recommended carrier separation between both the systems is presented in order to efficiently utilize the assigned frequency spectrum. Furthermore, for the cooperation in both the separated and the common radio bands, the necessary precautions are given for reaching the required isolation and thereby inter-system interference minimization.
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Multimedia data transmission in mobile networks and assurence of QoS
Bortel, Martin ; Novotný, Vít (referee) ; Havelka, Dušan (advisor)
In Bachelor’s Thesis - Multimedia Data Transmission over Mobile Networks and assurance of QoS basic characteristics of UMTS network are described. At the beginning of the thesis types of data and their properties are explained. Then the attention is paid to data transfers through the network and assurance of QoS. The principle of OSI model, function of RLC protocol and types of QoS classes are mentioned in this section. PDP Contexts and their application in the network are pointed out. At the end of the theoretical part the structure of network is described and the functionality of its parts is depicted. Closure of the thesis is focused on the simulations of UMTS network model in OPNET Modeler environment.
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Security system with mobile comunication
Novák, Petr ; Kučera, Pavel (referee) ; Macho, Tomáš (advisor)
The main aim of this work is to create such an electronical alarm system, which could be used at permanently or temporary inhabited areas or in cars. The advantage of this system is the possibility of the silent alarm, which is carried out by SMS. These messages are sent by to the owner or to the security company by GSM service. The first part of the project tries to solve the problem of guarded areas. It is necessary to deal with this problem, so that the system itself could work correctly. The second part describes the SMS contents and the way of communication between the microprocessor ATmega16 and the mobile phone Siemens C35 by AT commands. Up-to-date price comparison of these services, which are offered by mobile provider, are included in this part. The focus of the third part is hardware realisation of electronical alarm system. This part sloves connecting of battery backup, battery recharging in the mobile phone and analyses single sensors as well. In the last part the suitable algorithm with the help of a higher level programming language C is used for the microprocessor system.
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Measurement of mobile network parameters
Gábor, Tomáš ; Hanus, Stanislav (referee) ; Klozar, Lukáš (advisor)
This work deals with theoretical study and practical implementation of measurement and storing of mobile network parameters and following designing an programming web interface for their presentation. IT describes structure and development of GSM and UMTS networks. It also deals with satellite navigation system GPS and measuring module Telit UC864-G, which was used for measuring. The next step was to select a group of parameters that are important for calculating the quality of the signal path and to analyze process of storing the data into the database. In the end is completely described web interface and also all applied programming languages and methods.
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Simulation of UMTS system
Predajňa, Martin ; Prokopec, Jan (referee) ; Kejík, Petr (advisor)
The bachelor’s thesis deals with modeling of UMTS system in downlink. It is focused on signal processing in physical layer and observes BER depending on parameters of model of real environment by setting different interruption. Basic architecture of UMTS system, channel coding and multiplexing of transport channels to physical channels is described in this thesis. Radio frame structure for downlink dedicated physical data channel is also described there. Using of pseudorandom sequences in CDMA systems and their properties are key parameters for observation of BER. Simulation uses single-user model in basic band, which enables to observe the influence of noise and narrowband jamming. These channel properties have impact on BER, which is used for evaluation of UMTS system. The orthogonality of sequences is influenced by multi access interference so detection of required signal (which uses correlation properties of spreading sequences) is limited.
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