pacchetto 7

Question 1

What is a window?

Answer 1

A window is a signal in time domain which is multiplied by the signal to be examined.
It follows that we have a convolution in the frequency domain.
Therefore windows act as frequency filters.

Question 2

Window properties

Answer 2

We know that any representation in the time domain or in the frequency domain have the same information.
If i modify the time signal, then i also modify the spectrum.

Question 3

Windows comparison

Answer 3

Rectangular window: no weight applied, generally does’t cause leakage if no discontinuity exist but distorsion and leakage are evident in case of discontinuity.
Hanning window: spreads less energy, provide an attenuated spectrum but the shape is well conserved.