Hioki MEMORY HiCORDER 8855, Инструкция по эксплуатации

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4.8 FFT Analysis Function
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4.8.9 Cross Correlation [CCR]
Function
Rab (
τ
) =
-1
(Gab)
= Gab (
ω
)exp(j
ω
τ
)d
ω
Horizontal
cursor
Vertical
cursor
Stored waveform (input waveform) Stored waveform (output waveform)
Cross correlation function
Displays the degree of similarity between two points separated by a time
difference (
τ
) on two signals.
The degree of similarity is expressed as a function of the time difference (
τ
).
Major applications:
Obtaining the phase difference between two signals in time units.
Obtaining a speed or distance by measuring the time delay.
Time Time display. The center indicates the reference (
τ
=0), the
right side indicates time lag (+
τ
), and the left side indicates
time lead (-
τ
).
Linear Readings are from +1 to -1 (no units).
+1: the highest similarity between the input and output signals
for time differential
τ
, 0: the lowest similarity, -1: the polarity
is completely opposite
Example Cross correlation function waveforms