A
17
FFT Definitions
■
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. Low-pass filters used this way are called
anti-aliasing filters
.
The following figures show the effect of application of an anti-aliasing filter on a square wave input
waveform.
Without an anti-aliasing filter
Input time
waveform
Frequency
analysis results
Non-existent frequency components are observed
With an anti-aliasing filter
Input time
waveform
Frequency
analysis results
Appx.
Summary of Contents for MR8827
Page 19: ...14 Operation Precautions ...
Page 81: ...76 Start and Stop Measurement ...
Page 111: ...106 Manage Files ...
Page 125: ...120 Miscellaneous Printing Functions ...
Page 143: ...138 View Block Waveforms ...
Page 191: ...186 Setting Output Waveform Parameters ...
Page 291: ...286 FFT Analysis Modes Measurable Ranges With Octave Analysis 1 1 OCT 1 3 OCT ...
Page 292: ...287 FFT Analysis Modes 1 1 OCT 1 3 OCT 13 FFT Function ...
Page 293: ...288 FFT Analysis Modes 1 1 OCT 1 3 OCT ...
Page 295: ...290 FFT Analysis Modes ...
Page 309: ...304 Editor Command Details ...
Page 387: ...382 Module Specifications ...
Page 405: ...400 Dispose of the Instrument Lithium Battery Removal ...
Page 431: ...A26 FFT Definitions ...
Page 436: ......