Transfer function fitting from ASCII-data file

I use a network analyser to observe an electrical system. The network analyser provides an (ASCII-)table with the frequency as function of the power ratio and the phase difference. Now I would like to know if there is a function in Matlab to fit these data to obtain a transfer function of such electrical system.

Could someone help me with this?

thank you!

Answer 1

[Sebastian Castro]

If you have System Identification Toolbox, you can package up the frequency + complex response data in an idfrd container. The complex response can be found from the magnitude and phase.

After you have your data, you can estimate a transfer function with the tfest function in this toolbox.

- Sebastian

Answer 2

[dpb]

The Signal Processing Toolbox contains the function tfestimate and related friends...

Answer 3

[Bjorn]

Dear dpb,

The problem is that I cannot use the function tfestimate, because my data consists of the frequency associated with the transferred power (output/input) [dB] and phase difference (output-input) [deg].

I cannot find any function which transforms this data into a transfer function.

Did someone something similar like this before?