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Signal processing and receiving in UMTS system
Hron, Michal ; Hanus, Stanislav (referee) ; Kejík, Petr (advisor)
This semestral thesis be concerned with datailed analysis of receiving and processing signals in UMTS network system. Insistence of this work is setting to principals of RAKE receiver and processing signals in CDMA networks downlink channel. Through development system MATLAB simulates real function of RAKE receiver. This project is giving fundamental knowledges about receiving and processing of multipath signals to readers.
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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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Laboratory site for color measurement in video technology
Melo, Jan ; Kejík, Petr (referee) ; Slanina, Martin (advisor)
The diploma thesis is dividend into four parts. The first part describes basic terms in video technology (luminance, hue, diagrams CIE). The second part includes types of colour spaces RGB, HSV, CMY(K), YUV, YCbCr, YIQ. In the third and fourth part, these theoretical findings are used to propound laboratory observations. The laboratory observation processes the colour rendition of the colours in video technology. In the Matlab software, a user system environment was developed for operations with measured values. The software is capable of recalculating chromaticity coordinates between different colour spaces, to screen colours into diagrams CIE and to show the vectors of colours. The device used for measuring was Chromametr Konica Minolta CS-100A. A manual for the device was created. The laboratory observation was measured and processed in the form of a laboratory protocol.
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Radio Network LTE Design
Tribula, David ; Kejík, Petr (referee) ; Hanus, Stanislav (advisor)
The diploma thesis deals with the design of the LTE radio part using the ICS Designer program. First, the work describes the signal processing in the physical layer LTE system, for downlink and uplink. Subsequently, it was made simple block diagram. The next part deals with models of signal propagation in the radio environment. The last part is an introduction to the ICS Designer. This section describes the base station design and demonstration of some simulations. The last part is devoted to the design of the mobile network in the given area, its simulation and subsequent comparison with the existing mobile network.
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Signal Processing in Flarion System
Szajkó, Juraj ; Kejík, Petr (referee) ; Hanus, Stanislav (advisor)
Cílem bakalářské práce Zpracování signálů v systému Flarion bylo prostudovat způsoby zpracování signálu ve fyzické vrstvě a architekturu sítě Flarion. Na základě získaných poznatků při studiu fyzické vrstvy bylo za úkolem sestavit v prostředí Matlab model systému a simulace BER v závislosti na poměr vysílaného výkonu a výkonu rušivého signálu. V první části práce je detailní popis fyzické vrstvy Flarionu, probrána je baseband a OFDM modulace, LDPC kódování a frekvenční skákání. V druhém části práce je prostudována architektura sítě, ekvalizace, řízení výkonu, radiových zdrojů, a způsob handoffu. Ve třetí části práce je vytvoření downlink a uplink modelu v Matlab, dále je provedena simulace BER v závislosti na poměr vysílaného výkonu a výkonu rušivého signálu.
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Optimization of Access to CDMA Networks
Kejík, Petr ; Masopust, Jiří (referee) ; Wieser, Vladimír (referee) ; Hanus, Stanislav (advisor)
The aim of this dissertation thesis is an optimization of access to CDMA networks. To be more specific, this thesis deals with an optimization of admission control in UMTS network. The first part of the thesis deals with the present progress of the particular topic. Thereinafter there is an analysis of admission control in UMTS system. An own UMTS simulation program was created in MATLAB. This program enables implementation and simulation of the selected admission control algorithms. The thesis is focused on load factor based, fuzzy logic based and genetic algorithms. The created UMTS simulator was used for the mutual comparison of all algorithms. The aims of this thesis are the suitable UMTS model design, evaluation and possible optimization of selected algorithms.
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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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Coexistence of the communication systems in ISM band
Nowak, Dan ; Kejík, Petr (referee) ; Prokopec, Jan (advisor)
The purpose of this work is to study the physical layer technology of the communication systems working in the ISM band, to describe coexistence mechanisms in the selected frequency band, consequently to create models of the physical layers in the Simulink interface, to simulate synchronous transmission of the devices and to modify the model in order to correspond with coexistence mechanisms described in IEEE standard 802.15.2. The practical part of this paper examines the effect of Wi-Fi device output power on the transmission speed during synchronous transmission with Bluetooth device.
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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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E-UTRAN Air Interface Description
Opletal, Prokop ; Kejík, Petr (referee) ; Hanus, Stanislav (advisor)
The aim of this bachelor’s thesis was to study a basic principles of wireless system LTE with a view to radio interface. Readers are familiarize with a basic concepts of system within a text, like modulation OFDM, which is principal for LTE technology. Further in text are shortly describe OFDMA and SC-FDMA technologies, which are employ in LTE downlink and uplink. There are also summarize parameters, which radically change a bit rate in LTE systems. In dependence on the theoretic knowledge was designed a model of LTE system in MATLAB. With this model were performed simulations of transmission of LTE signal through the radio channel.
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