119
────────────────────────────────────────────────────
8.1 Overview of the FFT Function
────────────────────────────────────────────────────
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
NOTE
Chapter 8
FFT Function
8.1 Overview of the FFT Function
The FFT function has the following features.
(1) FFT (Fast Fourier Transform) processing can be performed on input signal
data for frequency analysis.
(2) Frequency range
133 mHz to 400 kHz
(3) Frequency resolution
1/400, 1/800, 1/2000, 1/4000 of frequency range
(4) 12 types of analysis functions
Storage waveform, linear spectrum, RMS spectrum, power spectrum, auto-
correlation function, histogram, transfer function, cross-power spectrum,
cross- correlation function, unit-impulse response, coherence function, octave
analysis
(5) Analysis modes
1-channel FFT, 2-channel FFT
(6) Analysis of data stored with memory recorder function and recorder and
memory function possible
(7) Switchable antialiasing filter
Automatic selection of cutoff frequency to match frequency range (8938 FFT
ANALOG UNIT)
・We recommend using an input unit equipped with an anti-aliasing filter that
can be enabled to minimize sampling distortions during FFT analysis.
・Refer to Appendix 3.10, "FFT Function" for more information about aliasing
distortion and anti-aliasing filters.