- FT - Fourier Transformation
- STFT - Short Time Fourier Transformation
- WT - Wavelet Transformation
- HHT - Hilbert-Huang Transformation
During my studying on sEMG decomposition, signal processing method is a good way to dig more useful information that is buried in weak sEMG signal.
FT, is a good way to reveal Frequency-domain information, but eliminate all time-domain information;
STFT, which was proposed after FT, continues to have time-domain information with a Short-Time sliding window algorithm. However, its fixed sliding window length limits the resolution of both time and frequency domain.
WT, which is regarded as a multiresolution analysis method, is proposed. Scaling and wavelet functions continue to have changing resolution in different frequency.
HHT, is another way to treat signals. EMD - emperical modes decomposition, as the core of HHT, has been conducted in many field.