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LTE system models
Navrátil, Petr ; Masopust, Jiří (referee) ; Hanus, Stanislav (advisor)
Master’s thesis is focused on part of mobile network named LTE. Project is analyzes the LTE physical layer, which is divided into four basic parts: Physical channels and modulation, Multiplexing and channel coding, Physical layer procedures, Physical layer measurements. Every part is described by actual 3GPP standard [1]. To understand the problem is expected a reader basic knowledge of OFDM systems, which the LTE system uses. The next part of this master’s thesis is dedicated to mathematic model physical layer of system LTE, created by program Matlab. This model is designed to measure errors in data transmission.
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Interference locator for EGSM and UMTS frequency bands
Predajňa, Martin ; Nováček, Zdeněk (referee) ; Hanus, Stanislav (advisor)
Diploma thesis describes direction finding principles for passive localization of emitting source. Direction finding system with one rotating antenna was chosen with triangulation calculation of emitter position. Input parameters are position of measurement point and direction of maximum signal receiving level. A suitable digital compass module and GPS receiver module for this measurement was chosen. For this purpose was created a graphic user interface, which allow user to communicate with external devices and control spectrum analyzer. Results of measurements are displayed at map, together with area of possible positions of transmitter. Receiving Yagi antenna is placed on rotator and whole system is placed on roof of car. Whole system was construct and results of measurement are discuss here.
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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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Mobile internet principles
Jehličková, Lenka ; Fencl, Josef (referee) ; Hanus, Stanislav (advisor)
Thesis concerns with mobile communications theory with focus on data transfer. In the introduction the history, the origin and individual mobile systems generations are described. It is followed by detailed description of second, third and fourth generation mobile systems. Frequency band allocation, signal processing, the system architecture itself, security management and basic features are also discussed. The GSM system is described together with individual data transmission types based on circuit switching – CSD and HSCSD and packet switching – GPRS and EDGE. For UMTS, FDD and TDD modes are listed as well as changes in individual releases, corresponding technologies and provided services. Next, there is the description of LTE and WiMAX systems, together with their improvements whose are part of the fourth generation of mobile systems. Last of the described systems is the still work in progress HAPS, also known as the system of stratospheric platforms. In the end important parameters are summarized and systems are compared with each other.
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Signal processing in ZigBee system
Miloš, Jiří ; Bradáč, Zdeněk (referee) ; Hanus, Stanislav (advisor)
Master's thesis The Signal Processing in ZigBee System is focused on properties of Physical Layer of ZigBee (standard IEEE 802.15.4 - 2003). The work consists of three parts. The first part contains common view on using and properties of ZigBee. The next part focuses on the Medium Access Control Layer and in detail on the Physical Layer. There described signal processing in the Physical Layer in individual radio bands. The last part of the project contains the process of modeling in the MATLAB for both models of system ZigBee (bands 868/915 MHz and 2450 MHz). The last part of thesis deals with the simulations of BER depending on Carrier-to-Noise Ratio. Also examined the coexistence of systems operating in the same or a nearby frequency band. Based on the results of simulations there are given recommendations for the use of the ZigBee system in minimizing BER.
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High bit rate LTE mobile system
Ohera, Vlastimil ; Kejík, Petr (referee) ; Hanus, Stanislav (advisor)
Aim of thesis was to acquaint with architecture and process of signal in systems using broadband LTE wireless technology. Thesis in detail is described physical layer of system. Next there is described comparison of LTE and WiMAX and table with all present systems. Thesis also is contained information about tested LTE system in real traffic. Next aim was created simulation of LTE system in downlink and uplink. Interface was created for easier configuration of each characteristics of transfer and type of interference of useful signal. This interface is contained control of whole simulation and presentation of measured values. Measured data were processed into graphs, which show dependence of error rate BER on C/N of useful and interference signal.
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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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T-Speed Test for UMTS System
Šmíd, Jan ; Kejík, Petr (referee) ; Hanus, Stanislav (advisor)
The thesis deals with adding new parts to program for measuring data rates in mobile communications. New program parts are used for analyzing web pages and HTTP protocol, recieving position data from GPS reciever and for creating automated measuring sequences.
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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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