FRF- Phase difference
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)
12.seproj 419 KB
1.JPG 183 KB
2.JPG 177 KB
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.
NI Sound and Vibration