13.3 Setting FFT Analysis Conditions
214
The window function defines the segment of the input signal to be analyzed.
Use the window function to minimize leakage errors. There are three general types of window functions:
The non-rectangular window functions generally produce lower-level analysis results. By applying attenu-
ation correction, the attenuation introduced by the non-rectangular window functions can be corrected to
bring analysis results back to similar levels.
13.3.5 Setting the Window Function
• Rectangular Window
• Hann window
• Hamming window
• Blackman window
• Blackman-Harris window
• Flat top window
• Exponential window
1
Select the window function.
Move the cursor to the
[Window]
item.
Select
See:
2
If [Exponential] is the selected type
Set the attenuation coefficient (percentage).
Move the cursor to the
[Attenuation rate]
item.
Set the attenuation coefficient as a percentage.
3
Set attenuation correction.
Move the cursor to the
[Compensation]
item.
Select
Rectangular (default setting), Hanning, Hamming, Blackman, Black-
man Harris, Flat-top, Exponential
None
Attenuated window function values are not corrected.
(default setting)
Power
The window function multiplies the power levels of the time-do-
main waveform so that output levels are comparable to those
of a rectangular window.
Average
The window function multiplies the average value of the time-
domain waveform so that output levels are comparable to
those of a rectangular window.
Procedure
To open the screen: Press the
STATUS
key
→
[Status]
sheet
See:
To set from the Waveform screen (
Correction value
For the rectangular window function:
The correction value is always 1 (0 dB).
When the attenuation rate is 10%
10%
100%
Noise is suppressed in the attenuated wave-
form.
2
1
3
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Страница 18: ...Operating Precautions 8 ...
Страница 26: ...1 4 Basic Key Operations 16 ...
Страница 74: ...4 4 Waveform Observation 64 ...
Страница 98: ...5 5 Managing Files 88 ...
Страница 110: ...6 6 Miscellaneous Printing Functions 100 ...
Страница 126: ...7 8 Seeing Block Waveforms 116 ...
Страница 160: ...8 10 Making Detailed Settings for Input Modules 150 ...
Страница 198: ...10 6 Numerical Calculation Type and Description 188 ...
Страница 296: ...15 7 Controlling the Instrument with Command Communications LAN USB 286 ...
Страница 304: ...16 2 External I O 294 ...
Страница 362: ...Appendix 5 FFT Definitions A28 ...
Страница 368: ...Index Index 6 ...
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