svcvs is powerful in enabling time domain filter simulation with defined polynomial or pole/zeros. If my filter's transfer function doesn't easily fit to polynomial or pole/zero format, instead, I have the transfer function exported in text (gain vs. freq), is there a way to take in such info. and enable time domain filtering simulation?
If you have access to MATLAB, you can generate a pole/zero equivalent of a transfer function using 'rationalfit'. You can choose the order and see if the results are accurate.
You can also convert the transfer function to s-parameter (with standard terminations) and use nport with those s-parameters.
Depending on the frequency range over which you have the data(if the data has not rolled off to insignificant values at the end of the range), you can have problems with time-domain simulation(like the ones mentioned by Andrew Beckett).
(I posted this a while back, but looks like it was dumped as spam).