Diagnostika a detekce poruch prenosovych kanalu a signalu.

Abstract

This thesis deals with problems of error detection in transmission channels and signals. The introductory theoretical part of the work describes the principle of error detection in a diagnostic object and, further generally describes some deterministic methods for error detection. The next part of the work is aimed at analysis of sources of errors in signals during their transmission in transmission channels. Common methods of signal transmission and causes of error origin for individual types of transmission are described here. Further, the mathematical and physical model of the transmission channel is given and representative particular deterministic methods for detection of errors of signals and transmission channels are described. Neural networks and their application for detection of errors in signals are discussed in the 6. part of the work. An outline of different kinds of neural networks as well as possibilities of their use in the solved problems is given here. Use of neural networks for detection of errors in signals is analyzed in the application part of the work. Detection of errors is divided here into two phases - the localization phase and classification phase. The experimental part of the work is aimed at the project, realization and checking for the operation of a diagnostic system with use of neural networks for detection of errors of signals. First, a survey of the considered errors of signals and their classification into the individual categories is presented there. Localization and classification of errors in signals is described in the next part. The principle of generation of the difference vector and classification of errors with the use of the symptom analysis method in the difference vector was done. The method of analysis of a separated error part of a signal, is explained there. The principle of localization and classification of errors is introduced there with the use of examples of error detection in representative types of signals. As a practical application, the detection of errors in signals from tensometric measurements as well as from real audio signals is given in the thesis.Available from STL, Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi