Appendix 5 FFT Definitions
A
19
Appendi
x
Anti-Aliasing Filters ____________________________________________
When the maximum frequency component of the input signal is higher than one-
half of the sampling frequency, aliasing distortion occurs. To eliminate aliasing
distortion, a low-pass filter can be used that cuts frequencies higher than one-
half of the sampling frequency. Such a low-pass filter is called an anti-aliasing fil-
ter.
The following figures show the effect of application of an anti-aliasing filter on a
square wave input waveform.
Non-existent frequency components are observed.
Without an anti-aliasing filter
Input time
waveform
Frequency analysis
results
With an anti-aliasing filter
Input time
waveform
Frequency analysis
results
Summary of Contents for 8847
Page 1: ...MEMORY HiCORDER Instruction Manual 8847 December 2010 Revised edition 4 8847A981 04 10 12H ...
Page 2: ......
Page 18: ...Operating Precautions 8 ...
Page 26: ...1 4 Basic Key Operations 16 ...
Page 74: ...4 4 Waveform Observation 64 ...
Page 98: ...5 5 Managing Files 88 ...
Page 110: ...6 6 Miscellaneous Printing Functions 100 ...
Page 126: ...7 8 Seeing Block Waveforms 116 ...
Page 160: ...8 10 Making Detailed Settings for Input Modules 150 ...
Page 198: ...10 6 Numerical Calculation Type and Description 188 ...
Page 296: ...15 7 Controlling the Instrument with Command Communications LAN USB 286 ...
Page 304: ...16 2 External I O 294 ...
Page 362: ...Appendix 5 FFT Definitions A28 ...
Page 368: ...Index Index 6 ...
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