 Please compare these six windows. "Rectangle Window"(U_1) is
the best to find multiple frequencies which are very close to each other.
e.g. 2kHz and 2.4kHz.
We can say Blackman-Harris Window has high "Magnitude Resolution" and Rectangle Window has high "Frequency Resolution". Let's summarize merits/demerits of Window Functions.
| Windows |
Magnitude Resolution |
Frequency Resolution |
| Rectangle |
very low |
very high |
| Hanning |
high |
low |
| Hamming |
normal |
normal |
| Blackman |
high |
low |
| Blackman-Harris |
very high |
very low |
| Bartlett |
low |
high |
That's it for this tutorial. Window Functions need to be used according to your objectives. If you want to find tiny frequencies, Blackman-Harris is better. If you want to find multiple frequencies which are close to each other, Rectangle is better. If you can have only one Window Function, Hamming
might be better considering these balance.
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