25
Figure 1-17
Sample
Spectrum View
Setting Screen 1
Spectrum Bins
: It allows you to set the number of frequency bins into which
the spectrum is divided.
Window function
: It allows you to select one of the standard window
functions to reduce the impact of running on a time-limited waveform.
Table 1-3
Window Function Table
Window
Main peak
width
(bins @
-3dB)
Highest
side lobe
(dB)
Side lobe
roll-off
(dB/octave)
Description
Rectangle
0.89
-13.2
6
No
fading;
maximal
sharpness; used for short
transients
Blackman
1.68
-58
18
Often used for audio work
Blackman-
Harris
1.90
-92
6
Used for general purpose
Flattop
2.94
-44
6
Negligible pass-band ripple;
mainly used for calibration
Gauss
1.33
to
1.79
-42 to -69
6
Gives minimal time and
frequency errors
