Howtosignalprocessing
- What is FFT overlap?
- Why do we use overlap in FFT?
- What is meant by short-time Fourier transform?
- How do you calculate short-time Fourier transform?
What is FFT overlap?
FFT convolution uses the overlap-add method together with the Fast Fourier Transform, allowing signals to be convolved by multiplying their frequency spectra. For filter kernels longer than about 64 points, FFT convolution is faster than standard convolution, while producing exactly the same result.
Why do we use overlap in FFT?
FFT processing can be particularly problematic when the signal consists of randomly occurring transients superimposed on a more continuous signal. Overlap processing is commonly used in this situation to improve the estimates.
What is meant by short-time Fourier transform?
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.
How do you calculate short-time Fourier transform?
In practice, the procedure for computing STFTs is to divide a longer time signal into shorter segments of equal length and then compute the Fourier transform separately on each shorter segment. This reveals the Fourier spectrum on each shorter segment.
