The initial part of my work is dedicated to overall introduction into the transmission systems and its categories. Further the work is focused on dividing of security codes which are used for transmission systems. In the next chapter is analyzed the problems of error origin, mathematical transcription of errors, categorizing of errors which can generate during transmission. The following chapter deals with description of convolutional codes describing security against errors, principle of serial consecution interpretation on parallastic consecution and visa versa. Here is outlined problems of convolutional codes input. In the next part are mentioned three convolution codes which are used for security against burst errors. In the next chapter is mentioned problems of message interleaving and description of used methods, how they originate and detailed description, how the errors are eliminated with the help of long segment interleaving. In the next chapter are described techniques which are used for clustered errors suppression. The last chapter is dedicated to the practical part of my thesis. There are detail descriptions and simulation techniques how the security of non-secure section is developed, transmission on line, burst errors induction on transmitted secure data and consecutive amendment or clustered errors division in transceiver. For the simulation there were utilized three convolutional codes for clustered errors amendment and two interleaving techniques.

The master's thesis solve the problem of setting new TCP variants for high-speed IP networks. The first goal was to describe in detail the behaviour of TCP and then analyse a problem of utilization the available bandwidth with standard TCP in high-speed network. Work consequently deals with selection and description the most perspective ones. Further the reader is familiarized with reasonable simulation tools of existing problems and their brief description. Main part of this thesis presents examination of performance of new TCP variants for high-speed network. During the examination the aspects on efficiency and fairness of competition flows on shared bottleneck are taken. The results are tabularly displayed plus compared with each other.

This thesis concludes a description of construction and functions of Electronically commutated motors. The main target is modelling of thermal field of Electronically commutated motors. For modelling was chosen Ansys Workbench setting with CAD geometry. There was a measurement for verifying result of simulation, and its proof is described in my thesis. This project also concludes comparison of results from simulation itself and results obtained from measuring thermal profile of EC motor.

Subject of this thesis is elemental description of DVB digital television and digitalization process of its terrestrial transmission according to DVB-T standard. The thesis characterizes in detail RF transmission channels used for wireless distribute of television. These channels ale mathematically described and their effect to OFDM signal is simulated in the MATLAB environment. It was created application with graphical user interface by this environment. Using simple setting of DVB-T and transmission channel parameters in the application user can simulate selective fading. Results of simulations with various settings are compared and analysed.

Diploma thesis is concerned with programming of AVR microprocessors. Main task was development of compact environment where user can learn methods necessary for successful programming of microprocessor. It was necessary to make an application enabling interactive simulation of processor to reach this goal. User-friendly control, simplicity and low hardware demands are main advantages of this application. Only computer with internet connection is demanded. Complicated installation, usual for similar products, is avoided.

This thesis deals with the exploration of possibilities of LAN analysis with the use of the hardware analyzer Finisar TGHs from the Finisar Corporation Company. As a monitored network was choosed the local computer network in the laboratory PA-249 at the Department of Telecommunications, which is located at the Faculty of Electrical Engineering and Communication, Brno University of Technology. All results acquired from the complex long-term monitoring of the choosed LAN network are described in this thesis. Further, the thesis is focused on the simulation and analysis of the model of this network that was created in the simulation environment Opnet Modeler. The data obtained from the real LAN monitoring were used as a basis of an operating simulation of the transmission abilities and features of the real LAN network. The last part of the thesis describes the verification of the transmission capabilities and characteristics of the real LAN. Verification was performed in Opnet Modeler, where the network has been analyzed in detail.

This thesis describes a protocol for the multiple data collection system and his implementation into Network Simulator 2 environment. The system defines two communication units. CU central unit and measuring unit MU. The units operate according to the rules defined by communication protocol. The content of this work is as follows. At the beginning is described the simulation tool, namely a system NS-2 and a tool for visualization of simulation results, the NAM. This is followed by a description of the proposed protocol, his principle of functions, units description and communication messages. The method of communication between units. Mainly was described the multicast and the types of multicast ASM and SSM. Additionally, was described the principle of unicast communication. This is followed by chapter describing methods of enlargement simulator. Adding an own protocol and support of multicast communication SSM. Adding a new protocol is represented by programming a new agent, a new application and a new protocol header definition. In this chapter are also described the necessary changes in the source files that are need to the recompilation. The main objective of this thesis is own implementation of the proposed protocol. In the programming language C++ were created two agents who represent a central and a measuring unit. These agents were compiled into a simulator and by using a simple script have been tested for functionality. The simulation script define MU 200 and one unit CU. Conclusion of work is devoted to simulation the load line between the central unit and "access" node. It was examined whether the use the method of cumulative acknowledgement saves the transmission capacity of line compared to normal method acknowledgement.

This master’s thesis is about replace voltage feedback operation amplifiers (VFOA) by current operational amplifiers (COA), current conveyors and current followers (CF). In introduction are mentioned word or two about operational amplifiers and their basic circuit such as invert and non-invert amplifier and there are described formulas for calculation gain. In another chapter is described COA, his properties and advantages compared to VFOA. Next there are described basic circuits of current conveyors. Follows chapter where is described replace VFOA by COA and conversion between them. In another part is at first deal with models of COA and CF in simulating program and then replace VFOA by COA. There are some simple circuits for example precision rectifiers and function generators and their simulations before and after replace VFOA by COA. In full-wave rectifier with current conveyors is made detailed simulation with some input voltages and frequencies. In last chapter is detailed described multi-mode rectifier with current follower. There is table witch described all modes of rectifier. For example voltage mode, current mode and mixed mode with half- or full-wave rectifier. There are simulations for all modes. Primarily are made detailed simulations voltage and current mode. In another part of this chapter is made measurement voltage and current mode. There are measured functions as half- and full-wave rectifier. There are described parameters of rectifier from measured values. In the end are these values compared with values from simulations.

This thesis concisely describes essential type of modulation technique for transmission of binary signal. In introductory part there are summarized advantages and disadvantages for each described modulation technique. There are described proceeding of modulation and demodulation too. Next part is specialized mainly to determination of incorrect receiving probability. For each modulation technique are calculated theoretical values of bit error rate and compiled graph. In practical part there are described possibilities of Matlab platform for measurement of bit error rate. In implement Simulink there is built model of communication channel with additional AWGN channel. Graphs are constructed from simulation data by the help of model’s control script. On selected modulation technique are inspected various elements which are reacted with graph. In finale part there are compared theoretical and measured values and summarized analysis.

Thesis deals with multicast broadcasts, discusses the type of ASM and SSM. Also deals with the principle of RTP / RTCP protocol for large multicast groups, for example, broadcasting IPTV. It was created a model for simulating the behavior of the network load in a large number of receivers. The application was developed in Java and uses the recommendations of RFC3550. There are also analysed processes of communication, initialization, log out, the structure of the data packets and signaling packets. The system is designed that can simulate multicast network and obtain the estimated parameters of the operation, or can operate in real traffic, for example, as a third-party monitor. In both modes, the measurement was carried out model situations. The results of the measurements were then compared. Principle and system control was described in detail. Output measurements are graphically processed and included in the work.