MATLAB: FRF magnitude calculation


Hello all!
I have a question regading the caluculation of FRF magnitude spectra that I would really appreciate some help with.
I have a number of files, each containing single sided FRFs with the real part in the first column and the imaginary part in the second. The question is how to obtain the magnitude spectra. Does this work in the same way as for a FFT, i.e. i take abs(re+im), to get the magnitude, or do I simply extract the real part (first column) from the file?
This might seem as a trivial question, but I'm having real trouble finding a good answer.
Regards, Felix

Best Answer

  • Hi Felix, you should form complex numbers in MATLAB from the first and second columns and take the magnitude squared (if it is a power calculation) of those complex numbers.