Hilbert spectrum in the analysis of electromyographic signals

The thesis concerned the use of the Hilbert spectrum in the analysis of selected electromyographic (EMG) signals. The theoretical part presents basic information on the empirical mode decomposition (EMD) of a signal into intrinsic mode functions (IMFs). The instantaneous parameters of the IMF components are characterised and the method of visualising the Hilbert spectrum is presented. The practical part involved developing a GUI for displaying the analysed EMG waveform together with the extracted intrinsic mode functions, the Hilbert spectrum and the scalogram. Real EMG signals recorded from healthy subjects and from patients with myopathy or amyotrophic lateral sclerosis were used in the tests. The thesis presents the most important functions implemented in the program, together with code excerpts. The resulting Hilbert spectrum plots and scalograms of the analysed signals were subjected to a comparative analysis.