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Spread spectrum modulator
Lejsková, Alena ; Kováč, Michal (referee) ; Maršálek, Roman (advisor)
This thesis deals with a method of spectrum-spreading of the data signals transmitted in the radio channel. There exist three different ways of spreading application, they uses pseudorandom sequences and also orthogonal sequences. In these systems we can find various kinds of modulations, one of them (Quadrature Phase Shift Keying) is shown at the end of the thesis. Spectrum spreading orthogonal multiplex OFDM is based on this method. The thesis wants to present the principle of the spectrum spreading method and the description of systems, transmitters and receivers that are using this method.
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Methods of multiple access for terrestrial radio networks
Žák, Josef ; Novotný, Vít (referee) ; Havelka, Dušan (advisor)
The content of this work is focused on the methods of multiple access for terrestrial radio network. These methods are exploited by the systems second and third generation of mobile networks. Specification the basic characteristics these methods is responsible part for inquest the correspondent specificities. Reason is that, that the wireless mobile communication it is possible split by three generation. First is NMT, with analog frequency modulation, which dont make use already, because has considerable disavantages . Analysis second generation mobile systems GSM leads to determination to many advanta- ges hereof system, who be based on methods FDMA, TDMA, CDMA. Description these methods is specialized on their spreading properties. Third generation of mobile systems UMTS is characterized wideband technology WCDMA, making use two duplex methods (FDD, TDD). Both methods provide higher efficiency of recovery frequency spectrum . All the theoretical approaches are examined in the last part of this work.it´s then possible after complete analysis these methods, make a design and a realization. In this event was used the computer programme Matlab–Simulink for simula- tion of duplex method WCDMA-FDD. Evaluation of this technology provides confrontation with second generation GSM .
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RAKE receiver for the UMTS system
Koudela, Oldřich ; Gleissner, Filip (referee) ; Prokopec, Jan (advisor)
This thesis is focused on theoretical description of procedures which take place in the UMTS system when processing a signal, its spreading with modulation technique DS SS(direct sequence spread spectrum), and subsequent processing in the RAKE receiver. Another focus is made in the basic functions of a RAKE receiver: match filtering, descrambling, despreading and integration. Aditionally, this thesis is suplemented with the results of a RAKE receiver simulation for a small number of samples in the MATLAB software and creation of aplication that simulates the receiver and its results.
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RAKE receiver for the UMTS system
Koudela, Oldřich ; Gleissner, Filip (referee) ; Prokopec, Jan (advisor)
This thesis is focused on theoretical description of procedures which take place in the UMTS system when processing a signal, its spreading with modulation technique DS SS(direct sequence spread spectrum), and subsequent processing in the RAKE receiver. Another focus is made in the basic functions of a RAKE receiver: match filtering, descrambling, despreading and integration. Aditionally, this thesis is suplemented with the results of a RAKE receiver simulation for a small number of samples in the MATLAB software and creation of aplication that simulates the receiver and its results.
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Spread spectrum modulator
Lejsková, Alena ; Kováč, Michal (referee) ; Maršálek, Roman (advisor)
This thesis deals with a method of spectrum-spreading of the data signals transmitted in the radio channel. There exist three different ways of spreading application, they uses pseudorandom sequences and also orthogonal sequences. In these systems we can find various kinds of modulations, one of them (Quadrature Phase Shift Keying) is shown at the end of the thesis. Spectrum spreading orthogonal multiplex OFDM is based on this method. The thesis wants to present the principle of the spectrum spreading method and the description of systems, transmitters and receivers that are using this method.
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|
|
Methods of multiple access for terrestrial radio networks
Žák, Josef ; Novotný, Vít (referee) ; Havelka, Dušan (advisor)
The content of this work is focused on the methods of multiple access for terrestrial radio network. These methods are exploited by the systems second and third generation of mobile networks. Specification the basic characteristics these methods is responsible part for inquest the correspondent specificities. Reason is that, that the wireless mobile communication it is possible split by three generation. First is NMT, with analog frequency modulation, which dont make use already, because has considerable disavantages . Analysis second generation mobile systems GSM leads to determination to many advanta- ges hereof system, who be based on methods FDMA, TDMA, CDMA. Description these methods is specialized on their spreading properties. Third generation of mobile systems UMTS is characterized wideband technology WCDMA, making use two duplex methods (FDD, TDD). Both methods provide higher efficiency of recovery frequency spectrum . All the theoretical approaches are examined in the last part of this work.it´s then possible after complete analysis these methods, make a design and a realization. In this event was used the computer programme Matlab–Simulink for simula- tion of duplex method WCDMA-FDD. Evaluation of this technology provides confrontation with second generation GSM .
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