#### exp

##### Full Member level 1

So the input impedance contains a frequency dependent resistance. But what does this really mean? Writing the transfer function, it becomes clear that it consists of non-conjungate complex coefficients. This system produces a complex output from a real input. That makes no sense whatsoever!

What is a frequency-dependent resistance to begin with: Can it be physical, how to deal with it?

In this example, I have the gut feeling that it is just an approximated model. Indeed, if I just take the magnitude of the complex coefficients and look at the magnitude response it is reasonably similar....