|
|
Measurement of diversity broadcasting in DVB-T2 standard
Koblischka, Vítězslav ; Kratochvíl, Tomáš (referee) ; Polák, Ladislav (advisor)
This bachelor thesis compares standards for digital and terrestrial television broadcasting of first-generation DVB-T and second-generation DVB-T2. It focuses particularly on the impact of interference in transmission media simulated by transmission channels for fixed, portable and mobile reception of terrestrial digital signal. Furthermore, the thesis compares SISO broadcast with the diverse MISO broadcast in DVB-T2 standard and evaluates the impact of the mode on error rate depending on the selected transmission channel and systems parameters that were used.
|
|
|
Model of physical layer of communication system IEEE 802.11ah
Jurák, Petr ; Staněk, Miroslav (referee) ; Polák, Ladislav (advisor)
This diploma thesis deals with the analysis of the IEEE 802.11ah wireless communication system. For such a purpose, an appropriate simulation model in program environment MATLAB is created. The first part of thesis focuses on the IEEE 802.11 standard. Basic blocks of the transmitter and receiver are described. Attention is also devoted on the brief description of considered transmission channels. The second part contains the description of the proposed and realized simulation model in MATLAB. Individual blocks of the simulation model are described in details. Finally, the obtained simulation results are evaluated and discussed.
|
|
|
Simulation of UMTS system
Predajňa, Martin ; Prokopec, Jan (referee) ; Kejík, Petr (advisor)
The bachelor’s thesis deals with modeling of UMTS system in downlink. It is focused on signal processing in physical layer and observes BER depending on parameters of model of real environment by setting different interruption. Basic architecture of UMTS system, channel coding and multiplexing of transport channels to physical channels is described in this thesis. Radio frame structure for downlink dedicated physical data channel is also described there. Using of pseudorandom sequences in CDMA systems and their properties are key parameters for observation of BER. Simulation uses single-user model in basic band, which enables to observe the influence of noise and narrowband jamming. These channel properties have impact on BER, which is used for evaluation of UMTS system. The orthogonality of sequences is influenced by multi access interference so detection of required signal (which uses correlation properties of spreading sequences) is limited.
|
|
|
Demonstration of optimal receivers for the AWGN channel
Musil, Petr ; Šilhavý, Pavel (referee) ; Číž, Radim (advisor)
This thesis deals with the demonstration of bit error rate reduction techniques. In the theory section, different techniques of bit error rate reduction are presented, followed by the introduction of the communication channel and the communication system parameters. Each technique is simulated in Matlab Simulink environment using the additive white Gaussian noise channel model. The simulations are captured in waveform oscillograms of all the signal processing stages. The practical section of this thesis offers a functional laboratory solution demonstrating different ways of transmission: a direct-path signal, a path with a cross-correlation receiver and a path using matched filtering. The individual circuits are described in detail, including waveform oscillograms of the signal processing blocks for illustration. Furthermore, the practical section presents printed circuit boards designs, comprehensive documentation for production, measurement results and a sample laboratory protocol.
|
|
|
Technology of Receiving of Very Weak Signals from Interplanetary Spacecrafts
Špaček, Jiří ; Bezoušek, Pavel (referee) ; Kovář, Pavel (referee) ; Kasal, Miroslav (advisor)
The work deals with the problematics of receiving very weak radio signals and it is focused especially on systems for low rate telemetry with carrier-subcarrier modulation. The part of this work is dedicated to calculation the link budget of typicall telemetry data transmission system between the Mars and the Earth in respect of the receiving equipment, which could be developed in the Experimental sattelites laboratory on the Institute of radio electronics BUT. The main part of this work is dedicated to developing and testing the low rate telemetry data transmission system model. The model is developed for the purpose of study the effects of AWGN and phase noise on the whole system and also on its component parts. The model has been developed and described in the way of easy parameters modification. The design for each parameter of the model is described carefully. With the developed model, the study of the effects of AWGN and phase noise on the whole system and also on its component parts has been performed.
|
|
|
Studies of Influences of Oscillators Frequency Instabilities in Satellite Communication Systems
Baran, Ondřej ; Baláž, Igor (referee) ; Šimša, Jan (referee) ; Kasal, Miroslav (advisor)
The dissertation thesis deals with a study of an influence of a simultaneous incidence of an additive thermal noise and a multiplicative phase noise on the useful signal transmission in narrowband satellite communication systems. While the additive thermal noise affects the useful signal only on the receiver side of the communication system, the multiplicative phase noise is produced in all system oscillators. One investigates how the receiver filter bandwidth reduction takes effect on the influence of individual noise types. The thesis is divided into four units. The first one (chapters 4 and 5) solves the ways of modeling of both noise types. In the second part (chapter 6), on the simple example, the primary analysis of the phase noise influence is made. Basic modulation schemes used in the satellite communication are also discussed (chapter 7). Third part (chapter 8) is devoted to the modeling of a general digital system with a M PSK modulation made directly on the main carrier wave. The last part (chapter 9) describes the modeling of a digital system with a BPSK modulation on the auxiliary subcarrier wave followed by an SSB modulation on the main carrier wave. General conclusions are deduced from obtained simulation results.
|
|
|
Demonstration of optimal receivers for the AWGN channel
Musil, Petr ; Šilhavý, Pavel (referee) ; Číž, Radim (advisor)
This thesis deals with the demonstration of bit error rate reduction techniques. In the theory section, different techniques of bit error rate reduction are presented, followed by the introduction of the communication channel and the communication system parameters. Each technique is simulated in Matlab Simulink environment using the additive white Gaussian noise channel model. The simulations are captured in waveform oscillograms of all the signal processing stages. The practical section of this thesis offers a functional laboratory solution demonstrating different ways of transmission: a direct-path signal, a path with a cross-correlation receiver and a path using matched filtering. The individual circuits are described in detail, including waveform oscillograms of the signal processing blocks for illustration. Furthermore, the practical section presents printed circuit boards designs, comprehensive documentation for production, measurement results and a sample laboratory protocol.
|
|
|
Model of physical layer of communication system IEEE 802.11ah
Jurák, Petr ; Staněk, Miroslav (referee) ; Polák, Ladislav (advisor)
This diploma thesis deals with the analysis of the IEEE 802.11ah wireless communication system. For such a purpose, an appropriate simulation model in program environment MATLAB is created. The first part of thesis focuses on the IEEE 802.11 standard. Basic blocks of the transmitter and receiver are described. Attention is also devoted on the brief description of considered transmission channels. The second part contains the description of the proposed and realized simulation model in MATLAB. Individual blocks of the simulation model are described in details. Finally, the obtained simulation results are evaluated and discussed.
|
|
|
Measurement of diversity broadcasting in DVB-T2 standard
Koblischka, Vítězslav ; Kratochvíl, Tomáš (referee) ; Polák, Ladislav (advisor)
This bachelor thesis compares standards for digital and terrestrial television broadcasting of first-generation DVB-T and second-generation DVB-T2. It focuses particularly on the impact of interference in transmission media simulated by transmission channels for fixed, portable and mobile reception of terrestrial digital signal. Furthermore, the thesis compares SISO broadcast with the diverse MISO broadcast in DVB-T2 standard and evaluates the impact of the mode on error rate depending on the selected transmission channel and systems parameters that were used.
|
|
|
Technology of Receiving of Very Weak Signals from Interplanetary Spacecrafts
Špaček, Jiří ; Bezoušek, Pavel (referee) ; Kovář, Pavel (referee) ; Kasal, Miroslav (advisor)
The work deals with the problematics of receiving very weak radio signals and it is focused especially on systems for low rate telemetry with carrier-subcarrier modulation. The part of this work is dedicated to calculation the link budget of typicall telemetry data transmission system between the Mars and the Earth in respect of the receiving equipment, which could be developed in the Experimental sattelites laboratory on the Institute of radio electronics BUT. The main part of this work is dedicated to developing and testing the low rate telemetry data transmission system model. The model is developed for the purpose of study the effects of AWGN and phase noise on the whole system and also on its component parts. The model has been developed and described in the way of easy parameters modification. The design for each parameter of the model is described carefully. With the developed model, the study of the effects of AWGN and phase noise on the whole system and also on its component parts has been performed.
|
guest ::
