FRF- Phase difference

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Hi,
I have acquired the input and output of my DUT. Both of them are as time-wave (Voltage).
The input is from a function generator, and the output from a photodiode.
Now I want to obtaine the FRF and phase difference vetween these two waves, Does anyone know how can I do that?
Also, I have performed the sweep by the Function generator, too. so the input is Swept-freq.
I have attached the project (Sound and vibration toolkit)
Thanks
Petar
Attachments:
12.seproj ‏419 KB
1.JPG ‏183 KB
2.JPG ‏177 KB
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Replay

For each bin frequency the Frequency Response Step returns the magnitude and phase of the response signal / stimulus signal. Your project already had this step. Only the data saved as a log in the project was available for us to look at. Using a Power Spectrum Step, it appears that you configured your sweep to output a signal from 10 Hz to 100 Hz, so that is the region of the FRF that we should examine. Because you are using a sweep, change the window in the Frequency Response Step to None.
You may want to perform a longer sweep to improve frequency resolution and/or average several sweeps to maximize signal-to-noise ratio.
Doug
NI Sound and Vibration