- Tytuł:
- Joint time-frequency and wavelet analysis - an introduction
- Autorzy:
-
Majkowski, A.
Kołodziej, M.
Rak, R. J. - Powiązania:
- https://bibliotekanauki.pl/articles/220841.pdf
- Data publikacji:
- 2014
- Wydawca:
- Polska Akademia Nauk. Czytelnia Czasopism PAN
- Tematy:
-
frequency analysis
time-frequency analysis
short-time Fourier transform
Gabor transform
Wigner-Ville transform
Cone-Shaped Transform
wavelet analysis
time-scale analysis
wavelet decomposition
filter banks
wavelet packets - Opis:
- A traditional frequency analysis is not appropriate for observation of properties of non-stationary signals. This stems from the fact that the time resolution is not defined in the Fourier spectrum. Thus, there is a need for methods implementing joint time-frequency analysis (t/f) algorithms. Practical aspects of some representative methods of time-frequency analysis, including Short Time Fourier Transform, Gabor Transform, Wigner-Ville Transform and Cone-Shaped Transform are described in this paper. Unfortunately, there is no correlation between the width of the time-frequency window and its frequency content in the t/f analysis. This property is not valid in the case of a wavelet transform. A wavelet is a wave-like oscillation, which forms its own “wavelet window”. Compression of the wavelet narrows the window, and vice versa. Individual wavelet functions are well localized in time and simultaneously in scale (the equivalent of frequency). The wavelet analysis owes its effectiveness to the pyramid algorithm described by Mallat, which enables fast decomposition of a signal into wavelet components.
- Źródło:
-
Metrology and Measurement Systems; 2014, 21, 4; 741-758
0860-8229 - Pojawia się w:
- Metrology and Measurement Systems
- Dostawca treści:
- Biblioteka Nauki