Howtosignalprocessing
- How does a Hanning window work?
- What is Fourier amplitude spectrum?
- How does windowing affect FFT?
- Why do we use Hanning window?
How does a Hanning window work?
HANNING is a window function for signal or image filtering using a fast fourier transform. By processing data through HANNING before applying FFT, more realistic results can be obtained. The window calculated by HANNING is basically the first half of a cosine—in other words, only the positive cosine values.
What is Fourier amplitude spectrum?
The Fourier amplitude spectrum FS(ω) is defined as the square root of the sum of the squares of the real and imaginary parts of F(ω). Thus: [2] Since a(t) has units of acceleration, FS(ω) has units of velocity. The Fourier amplitude spectrum is of interest to seismologists in characterizing ground motion.
How does windowing affect FFT?
You can minimize the effects of performing an FFT over a noninteger number of cycles by using a technique called windowing. Windowing reduces the amplitude of the discontinuities at the boundaries of each finite sequence acquired by the digitizer.
Why do we use Hanning window?
Leakage Reduction Choice of Window
The Hanning window is usually a good choice. The main advantage of controlling the leakage is an increase in the dynamic range of the analysis, as leakage may swamp signal components of close frequencies and much smaller magnitudes.
