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Wireless transmission interference modeling (AWGN, Rayleigh, Rice fading channels)
Hloušek, Tomáš ; Gleissner, Filip (referee) ; Mikulka, Jan (advisor)
This thesis describes and models wirelesss transmission intereferences in real communication channels. A signal received on a fading channel is subjected to a multiplicative distortion and to the usual additive noise. Real channel adds to the signal noise and fadings. Gaussian noise is a result of channel awgn. Fadings is implicated by multipath propagation of signal in Rayleigh and Rician channels. Main goal of this project is to program BERsolve, which is created in tool GUIDE in Matlab. User program BERsolve makes it possible to analyse bit error rate and symbol error rate for some types of channel models, which are defined by standard COST207. BERsolve offers some other functions i.e. display time behaviour, constellation diagram and spectrum. This program provides us with an overview representation of problem by multipath interferences in communication channels.
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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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GSM-EDGE and UMTS Systems Coexistence
Gleissner, Filip ; Hanus, Stanislav (advisor)
The dissertation thesis deals with the investigation of the coexistence of GSM–EDGE and UMTS systems with focus on the physical layer of the systems. The aim is to provide a set of recommendations for practical cooperation while the systems operate in both the separated and the common radio bands. A detailed description of signal processing of both the systems on the physical layer is presented. On the basis of this description, models of both systems were created and implemented in the MATLAB environment. The simulations are focused on the physical layer quality parameters, especially the bit error ratio evaluation for various ratios of useful signal power to noise power during the transmission over the radio channel. Simulation is also used to examine the quality of received useful signal while it is interfered by signals from the same and adjacent channels. The purpose is to determine the isolation between these adjacent channels, when the bit error ratio of the useful signal does not exceed a certain reference value. The simulation results are subsequently subjected to comparison with the results of the experimental measurements in laboratory conditions. Before the measurements are carried out, a study of possible interference types is performed. Consequently, the crucial parameters of the measuring equipment used are verified. From the results of simulations and measurements, the proposal of a minimum and recommended carrier separation between both the systems is presented in order to efficiently utilize the assigned frequency spectrum. Furthermore, for the cooperation in both the separated and the common radio bands, the necessary precautions are given for reaching the required isolation and thereby inter-system interference minimization.
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Cellular Network Coverage Model
Unzeitig, Lubomír ; Mikulka, Jan (referee) ; Gleissner, Filip (advisor)
This work deals with a mobile signal propagation in electromagnetic wave form in a real environment of city microcell. The electromagnetic wave passing through the city environment is affected by many kinds of mechanism. It includes especially diffraction along vertical edges of buildings, diffraction across building roofs and buildings or ground refraction. These mechanisms are time variable. If we want to predicate them, we have to use sort of approached model. For an experimental part of this work, the Berg’s recursive model with a possibility of path loses or signal level prediction in a selected microcellular system is chosen. The software for a cellular network coverage is created on the basis of this fact. Its advantage is a possibility of up to five base stations placing and many kinds of settings, e.g. operating frequency, base station transmitting power, base and mobile station antennas height etc. There is a possibility of system GSM 900, GSM 1800 or UMTS choice. The Berg’s recursive model features are checked by simulations on experimental and real maps of build-up area.
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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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GSM-EDGE and UMTS Systems Coexistence
Gleissner, Filip ; Hanus, Stanislav (advisor)
The dissertation thesis deals with the investigation of the coexistence of GSM–EDGE and UMTS systems with focus on the physical layer of the systems. The aim is to provide a set of recommendations for practical cooperation while the systems operate in both the separated and the common radio bands. A detailed description of signal processing of both the systems on the physical layer is presented. On the basis of this description, models of both systems were created and implemented in the MATLAB environment. The simulations are focused on the physical layer quality parameters, especially the bit error ratio evaluation for various ratios of useful signal power to noise power during the transmission over the radio channel. Simulation is also used to examine the quality of received useful signal while it is interfered by signals from the same and adjacent channels. The purpose is to determine the isolation between these adjacent channels, when the bit error ratio of the useful signal does not exceed a certain reference value. The simulation results are subsequently subjected to comparison with the results of the experimental measurements in laboratory conditions. Before the measurements are carried out, a study of possible interference types is performed. Consequently, the crucial parameters of the measuring equipment used are verified. From the results of simulations and measurements, the proposal of a minimum and recommended carrier separation between both the systems is presented in order to efficiently utilize the assigned frequency spectrum. Furthermore, for the cooperation in both the separated and the common radio bands, the necessary precautions are given for reaching the required isolation and thereby inter-system interference minimization.
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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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Cellular Network Coverage Model
Unzeitig, Lubomír ; Mikulka, Jan (referee) ; Gleissner, Filip (advisor)
This work deals with a mobile signal propagation in electromagnetic wave form in a real environment of city microcell. The electromagnetic wave passing through the city environment is affected by many kinds of mechanism. It includes especially diffraction along vertical edges of buildings, diffraction across building roofs and buildings or ground refraction. These mechanisms are time variable. If we want to predicate them, we have to use sort of approached model. For an experimental part of this work, the Berg’s recursive model with a possibility of path loses or signal level prediction in a selected microcellular system is chosen. The software for a cellular network coverage is created on the basis of this fact. Its advantage is a possibility of up to five base stations placing and many kinds of settings, e.g. operating frequency, base station transmitting power, base and mobile station antennas height etc. There is a possibility of system GSM 900, GSM 1800 or UMTS choice. The Berg’s recursive model features are checked by simulations on experimental and real maps of build-up area.
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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.
|
|
|
Wireless transmission interference modeling (AWGN, Rayleigh, Rice fading channels)
Hloušek, Tomáš ; Gleissner, Filip (referee) ; Mikulka, Jan (advisor)
This thesis describes and models wirelesss transmission intereferences in real communication channels. A signal received on a fading channel is subjected to a multiplicative distortion and to the usual additive noise. Real channel adds to the signal noise and fadings. Gaussian noise is a result of channel awgn. Fadings is implicated by multipath propagation of signal in Rayleigh and Rician channels. Main goal of this project is to program BERsolve, which is created in tool GUIDE in Matlab. User program BERsolve makes it possible to analyse bit error rate and symbol error rate for some types of channel models, which are defined by standard COST207. BERsolve offers some other functions i.e. display time behaviour, constellation diagram and spectrum. This program provides us with an overview representation of problem by multipath interferences in communication channels.
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