Promax OD-603 Manual page 30

To select the FFT window
►
There are four FFT windows. Each one has trade-offs between frequency
resolution and magnitude accuracy. What you want to measure and your
source signal characteristics help you to determine which window to use.
Use the following guidelines to select the best window.
Type
Rectangle
Hamming
Hanning
June 2016
Characteristics
Best solution for frequency, worst for magnitude.
Best type for measuring the frequency spectrum
of non repetitive
frequency components near DC.
Recommend to use for:
Transients or bursts, the signal level before
and after the event are nearly equal.
Equal-amplitude
frequencies those are very close.
Broadband random noise with a relatively
slow varying spectrum.
Better solution for magnitude than Rectangle,
and good for frequency as well. It has slightly
better frequency resolution than Hanning.
Recommend to use for:
Sine, periodic and narrow band random
noise.
Transients or bursts where the signal levels
before and after the event are significantly
different.
Good for magnitude,
resolution than Hamming.
Recommend to use for:
Sine, periodic and narrow band random
noise.
Transients or bursts where the signal levels
before and after the event are significantly
different.
signals and measuring
sine waves
but poorer frequency
Window
with
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