User Manual

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21.3 Reference
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1.3.10 FFT Function
Time domai
n
Frequency domai
n
t
f
FFT
FFT stands for Fast Fourier Transformation, which is a calculation method
used to decompose a time-domain waveform into frequency components.
By performing FFT calculation, various calculations can be performed.
Concept of time domain and frequency domain
The signals measured by this memory recorder have values which correspond
to time, that is the signals are functions of time.
Waveform in the figure below is an example of such a signal.
Signals which are expressed as a function of time are called time domain
signals.
In reality, a signal consists of a number of sine-waves of different frequencies,
called frequency components, which combine to create the final shape of the
waveform. Expressing waveform the source signal, as a function of its
frequency components yields a frequency domain representation.
Often, the characteristics of a signal which cannot be easily analyzed in the
time domain, can be clearly revealed by the frequency domain representation.