frequency response and transfer function

[ankit]

Hi

What is the difference between transfer function vi in basic labiview frequency palette and FRF(Mag & Phase) vi in sound and vibration tool kit. Aren't the two vi's for the same purpose, but I am getting different results using these two vi's.

Which vi should be used for calculating transfer function between two signals x and y.

Ankit

[Jennifer O]

Hi Ankit,

You are correct that the FRF (Mag & Phase) VIs are very similar.  The one provided with the Sound and Vibration Toolset has several extra features such as the Spectrum Info output. 

For a given measurement with given settings you could choose either VI, however you should see the same result from both.  If you are not seeing the same result, I expect the input parameters are not identical.  Changining input parameters such as averaging can have significant impact on your results.  Verify that you have identical parameters and I expect you will be able to get your results to match.

Regards,

Jennifer O.
Applications Engineer
National Instruments