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Modelling of Network Coding in Wireless Networks
Svobodník, Petr ; Miloš, Jiří (referee) ; Kuder, Zenon (advisor)
During data exchange in the Point-to-Point wireless topology, in case where end nodes aren’t accessible directly, a relay is deployed. However, the basic approach to relays – Store-and-Forward – isn’t the way to reach the maximum throughput. Network Coding operation is performed by combining data words (packets) travelling through the network in opposite directions into one packet. End nodes, with knowledge of the data sent, can decode received packet. Packet exchange is then finished in shorter time which results in an increase of network throughput. There are more methods of Network Coding which differ from each other in the time requirements or the ability to work in a noisy channel. In this paper they will be described and compared.
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Microcontroller based system for voice transfer
Kapitančik, Maroš ; Kaczmarczyk, Václav (referee) ; Bradáč, Zdeněk (advisor)
The aim of this thesis have to introduce us with digitalized transmission of speech with limited data flow and construct device witch can comunicate on this level. Theoretical part is describing base creation of sound human preception and issues with digitizing. Proposed device uses hardware codec VS1063a. Coding is applied with IMA ADPCM. Scale of incoming analog audio signal can be up to 4kHz. Inside system is controled by microcontroler, witch take care about others parts. For comunication with other moduls is used wireless transceivers module. Software part describes confuguration and selected options of every individual part. Next is explained principle of entire system. For comunication was implemented packet data structure. This implementation raised data flow but saved error state in transmit.
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Microcontroller based system for voice transfer
Kapitančik, Maroš ; Kaczmarczyk, Václav (referee) ; Bradáč, Zdeněk (advisor)
The aim of this thesis have to introduce us with digitalized transmission of speech with limited data flow and construct device witch can comunicate on this level. Theoretical part is describing base creation of sound human preception and issues with digitizing. Proposed device uses hardware codec VS1063a. Coding is applied with IMA ADPCM. Scale of incoming analog audio signal can be up to 4kHz. Inside system is controled by microcontroler, witch take care about others parts. For comunication with other moduls is used wireless transceivers module. Software part describes confuguration and selected options of every individual part. Next is explained principle of entire system. For comunication was implemented packet data structure. This implementation raised data flow but saved error state in transmit.
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User Oriented QoS System
Plchot, Oldřich ; Matoušek, Petr (referee) ; Kašpárek, Tomáš (advisor)
This master's thesis deals with the possibilities how to guarantee the quality of service in the area of computer networks using a GNU/Linux operating system. This work compares and evaluates tools which are necessary to guarantee the quality of service. The goal of this work is to discuss the advantages and disadvantages of these tools and to design a system which handles the problem of quality of service. Designed system uses a heuristics, which allows the user to set up the quality of service system without studying specific properties of communication protocols on the network or application layer. This work also includes a theoretical introduction into the quality of service and computer networks.
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Control plane analysis in 4th generation mobile networks
Hajn, Pavel ; Novotný, Vít (referee) ; Krkoš, Radko (advisor)
The thesis is focused on the description of LTE system in terms of signaling on interfaces of LTE and EPC subsystems, such as UE initial network connection. The next section describes the types of diagnostic methods for mobile networks using OSS, drive testing and flow analysis. The thesis also aims at description of key performance indicators (independent service QoS parameters and the KPI for the radio part of the network). Part of the network measurement includes a description of the driver settings and views for analysis. It is also described the implementation of measuring and evaluating the results.
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Control plane analysis in 4th generation mobile networks
Hajn, Pavel ; Novotný, Vít (referee) ; Krkoš, Radko (advisor)
The thesis is focused on the description of LTE system in terms of signaling on interfaces of LTE and EPC subsystems, such as UE initial network connection. The next section describes the types of diagnostic methods for mobile networks using OSS, drive testing and flow analysis. The thesis also aims at description of key performance indicators (RSRP, RSSI, etc.) and the proposal for measuring of the LTE network physical layer and the data transmission speed.
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ZigBee implementation for Automotive Industry
Zatloukal, Martin ; Maršálek, Roman (referee) ; Prokopec, Jan (advisor)
This bachelor’s thesis describes possibilities of usage of ZigBee communication protocol in automotive industry, transport and logistics. Thesis also deals with ways of practical implementation of ZigBee protocol including typical cases solutions, designing and realization of necessary electrotechnical devices and modules followed by compilation of control software and experimental measurements of these devices in real traffic flow. In the first part of thesis, there are some basic features and parameters of ZigBee reminded, followed by ways of ZigBee communicator usage description and adumbrating how to perform integration with existing practical systems. The second part is about analysis of ZigBee data system construction, communication system scheme design and pre-projection of block schemes of its particular cells. The third part concretizes requested functions and features of these cells and describes ways of its hardware realization. The fourth section describes controlling software design, connection and controll of functions using PC and additional programs, using of X-CTU software offered by MaxStream Company to set up XBee parameters and using of AVR Studio 4 offered by Atmel Company to set up ATmega16 processor. The last part is taken by completation of hardware and software, tests with a few of XBee chips and network nodes in laboratory conditions and examples from the real traffic range measurement.
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Design and realization of wireless interface ODBII-XBee
Zatloukal, Martin ; Frýza, Tomáš (referee) ; Prokopec, Jan (advisor)
This master’s thesis describes possibilities of usage of ZigBee communication protocol and integrated circuit ELM 327 in problem of realization universal diagnostic device, running by OBDII communication standards, which can be used to monitor function of all car´s electronic systems. Thesis also deals with design and realization of necessary electro technical devices and modules followed by compilation of control software and experimental measurements of these devices in real traffic flow. In the first part of project, there are reminded some basic features and parameters of OBDII, followed by description of ways how to use OBDII and adumbrating how to realize universal diagnostic system. The analysis of ZigBee system focused on XBee circuits follows. Construction, ways of data transfer and possibilities of controlling are described. Integrated circuits produced by ELM Electronics Company are introduced and possibilities of usage ELM 327 are described as requested by main task. Second part talks about designing of electronic circuits of this system, assembling schematic diagram and designing sources for production of PCB. Physical realization of these circuits and its first start is also included. Thesis finishes by dealing with practical experiences and measurements using real vehicles. This part talks also about means to improve system by several software solutions to reach more effective functioning of created device.
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Modelling of Wireless Network Coding
Svobodník, P.
During data exchange in the Point-to-Point wireless topology, in case where end nodes aren’t accessible directly, a relay is deployed. However, the basic approach to relays – Store-andForward – isn’t the way to reach the maximum throughput. Network Coding operation is performed by combining data words (packets) travelling through the network in opposite directions into one packet. End nodes, with knowledge of the data sent, can decode received packet. Packet exchange is then finished in shorter time which results in an increase of network throughput. There are more methods of Network Coding which differ from each other in the time requirements or the ability to work in a noisy channel. In this paper they will be described and compared.
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