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Support of real-time services in recent 3G mobile networks
Vinkler, Lukáš ; Mácha, Tomáš (referee) ; Novotný, Vít (advisor)
This Master’s thesis is focused on the recent 3G mobile networks. The first chapter describes an evolution of standardization 3G and surveys a gradual development of 3G networks in Czech Republic from a point of view of commercially launched technologies and assigned frequency spectrums for single mobile operators. UMTS and CDMA 2000 are briefly approached in next subchapters. The subchapter CDMA 2000 is briefly concentrated on architecture and a physical layer of this technology and characterizes main features of four revises of developmental branch CDMA 2000 1x EV-DO. The subchapter UMTS is especially focused on a comparison of air interfaces TD-CDMA and W-CDMA. New features were implemented to the recent system UMTS for a better support of real-time services. These features increasing a throughput and decreasing a delay are described in a chapter Technology HSPA. This chapter chooses the most important features and describes changes (in a control and architecture) which had to be implemented. First chapter is finished by technology WiMAX. The most recent perspective cell systems are compared with WiMAX in this subchapter and qualitative parameters of WiMAX are shown there. The three different 3G technologies (UMTS-FDD, UMTS-TDD and CDMA 2000) are lunched in Czech Republic. The second chapter briefly compares coverage of three czech mobile operators (Telefónica O2, T-Mobile and U:fon) and then presents results of qualitative parameters of used 3G technologies. The simulation conducted by software IxChariot were focused on to gauge parameters like throughput, delay, jitter, lost data, MLR and DF. The conditions for providing real-time services were specified based on simulations that were practically checked. The lab composed in last chapter should bring closer to students technology UMTS-TDD launched by T-Mobile. The students will measure the qualitative parameters of this technology with the assistance of commonly available tools.
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QoS Assurance in UMTS Network
Fabricius, Marián ; Novotný, Vít (referee) ; Hošek, Jiří (advisor)
Diploma thesis deals with assign and distribution quality of service in mobile UMTS telecommunication networks. The project consists of two parts, theoretical and practical. Theoretical part of the project is focused to familiarize with functionality of the UMTS network with the main aspect at admission mechanism in radio part of the network as well as quality of service assign mechanisms according to service demands within core network of UMTS. Practical part of the project is given to simulation program OPNET Modeler and its capabilities in network design and testing various parameters of UMTS network with implementation quality of service mechanism. As the asset of diploma thesis becomes designed functional prototype of UMTS network with various options for individual settings user equipment as well as fixed mobile networks nodes.
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QoS in UMTS
Kavan, Radovan ; Hanus, Stanislav (referee) ; Kejík, Petr (advisor)
This thesis treats of QoS (Quality of Service) in UMTS system. The term quality of service is frequently used, recently, however not only in computer networks, but also more and more in mobile networks also. Present system of 2nd generation (2G) GSM enables only limited exploitation of QoS function. System UMTS is a system of 3rd generation (3G) already and contains quality of service in greater measure which is ensured with number of algorithms and functions. Individual QoS functions enable effective utilization of radio interface, support maintenance of planned coverage and offer high spectral efficiency. Functions that cater to quality of service are called RRM functions (Radio Resource Management). There exist five basic functions in UMTS system that are Admission control (AC), Power control (PC), Load control (LC), Handover control (HC) and Packet scheduler (PS). These functions are responsible for control of network access, control of power, control of network load, control of handover and packet (bit rate) scheduling. Last three functions are usually collectively designated as Congestion control, control of network overload. UMTS layer model, differentiation of services, traffic classes and 3GPP concept are also discussed. In thesis the attention is piad to Admission control algorithm – control of network access – in the uplink direction and to different ways of load (in the cell) modeling. Individual approaches are simulated in MATLAB. A possibility of using algorithm in the real system is discussed in conclusion.
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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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Multicast routing in UMTS technology
Kokeš, Roman ; Novotný, Vít (referee) ; Šimek, Milan (advisor)
This Master thesis is about multicast in mobile network 3rd generation UMTS(Universal Mobile Telecommunacitions System). UMTS network primary designs for data transfers and supports new services as real-time transfers of multimedia streams. This is reason why mobile network was equiped also with multicast service. When a lot of users want to receive same data (e.g. tv program) the network excessives load of transmission same data and the server have to keep connection to each user. Group 3GGP developed multicast service for UMTS, which name is MBMS (Multimedia Broadcast and Multicast Service). Thesis analyses function of this service in mobile network. First part describes basic principles of UMTS network and its structure. Next part focuses on change of main node (SGSN and GGSN) and of new node BM-SC(Broadcast-Multicast Service Center). This new node is main node for control of multicast transmission. BM-SC connects to server which provides multicast data for users and provisions individual phase of MBMS session. It was created new procedure which supports multicast session (e.g. Activate MBMS service). Next part focuses on GPRS Tunneling Protocol (GTP). This protocol is used for transfers control and user’s data in tunnels inside core network. This part describes structure of data and control messages. Last part analyzes multimedia transfers in UMTS with program Opnet Modeller.
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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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Acquisition of service information from current terminals of GSM and UMTS cell networks, service procedures for mobile terminals
Kříž, Jakub ; Skořepa, Michal (referee) ; Novotný, Vít (advisor)
This thesis concentrates on the UMTS cellular network and the possibilities of its monitoring. There are several methods of monitoring the UMTS. The technique used in this project is based on monitoring through a cellular terminal. The theoretical part is devoted to the description of the UMTS system and the WCDMA technique. The practical part then deals with the method of UMTS monitoring through a cellular terminal and describes in detail individual screens of the FTD (Field Test Display) program, the Netmonitor functions and their parameters. The next part of this thesis analyses the RRC messages, which were recorded during the realization of services (video calls, calls, data transfers) in the UMTS network. The last chapters of the thesis are briefly dealing with software and hardware servicing of cellular terminals. The attachment then offers two lab tasks, in which the students get acquainted with the UMTS network structure and the behaviour of the cellular terminal in this network.
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Planning of UTMS access networks
Spěváček, Jiří ; Kapoun, Vladimír (referee) ; Novotný, Vít (advisor)
The master thesis is focused on the Universal Mobile Telecommunications System (UMTS) - the third-generation cell phone technology. The first part describes the development of mobile networks and the structure of the UMTS. The second part, the main part of the thesis, is focused on the planning procedure of the UMTS access network. It consists of an explanation of the general planning procedure and a specific project designing the coverage of Pelhřimov surroundings. The final part of the thesis contains a laboratory problem including instructions.
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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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Analýza trhu vysokorychlostního připojení k internetu v ČR
Poloczek, Bronislav ; Toman, Prokop (advisor) ; Sigmund, Tomáš (referee)
The objective of the thesis is to provide a view of the situation in high-speed Internet connection in the Czech Republic. At the beginning we present a history of internet and describes in particular the most frequently used technology of high-speed connectivity to the Internet. This is followed by a comparison of the current supply and demand in a market of Internet connection in the Czech Republic. This study not only compare technological aspects, but takes into consideration the economic situation, government regulations and changes from 2009 as well. Finally, there is a summarization and an evaluation of the results and a reflection on possible future on a market of high-speed connection in Czech republic.
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