Stft matlab

1. What is STFT in MATLAB?
2. What is the difference between FFT and STFT?
3. Why do we use STFT?
4. What is the difference between STFT and wavelet transform?

What is STFT in MATLAB?

The short-time Fourier transform (STFT) is used to analyze how the frequency content of a nonstationary signal changes over time. The magnitude squared of the STFT is known as the spectrogram time-frequency representation of the signal.

What is the difference between FFT and STFT?

FFT has a resolution of 2048 lines, Blackman window, and 50% overlap and STFT also has Block size 2048, FFT size 16K, Blackman window used, and 50% overlap. As we can see, STFT performs better with the same block size (but more calculated lines). We improved frequency resolution for the same amount of scooped data.

Why do we use STFT?

STFT is widely used in audio feature extraction for time-frequency decomposition. This can be observed from the signatures in Tables V–VII. However, STFT provides only a suboptimal tradeoff between time and frequency resolution since the frequency resolution of the STFT is the same for all locations in the spectrogram.

What is the difference between STFT and wavelet transform?

In contrast to the standard STFT which uses a single window size, the wavelet transform (WT) uses short windows at high frequencies and long windows at low frequencies [21]. Wavelets rely on the use of a mother wavelet function that can be scaled and shifted, to correlate with the anomalies or events of the signals.