How to obtain FRF if sampling frequency for INPUT and OUTPUT data is different?

I am trying to compute FRF and then modal parameters using modalfrf and modalfit commands using data obtained from FE simulations. The load is applied for a certain time and then free response of structure is observed (as in case of impulse loading). Both sampling time and total time for load and response parameters (say displacment) are different. I can obtain FFT for these input and output separatey but can not get frequency response function as sampling time and total time is different. Is there any way to obtain FRF and modal parameters in such case?

Answer 1

[dpb]

You'll need to resample one or both to a corresponding time base.

This will introduce some error into the estimation; if the sampling rates aren't too markedly different it shouldn't be too bad.

[lekhani gaur]

Total time and sample time for input are 6E-3 s and 1E-6 s respectively while total time and sample time for ouptput are 0.5 s and 1E-3 s respectively. Even if I intorduce total time for input load as 0.5s same as output , (load F is defined for t<0.006s, and F=0 for t>0.006), the sample time still will be different as generating FE simulation's results at 1E-6 sample time is huge. Can we introduce different sample time for both input and output?