Newbie level 3
Z11 is more intuitive to me than Z21. Here I have a bilateral setup I want to find the Z parameters for. By definition Z11=V1/I1 (I2=0), so I think Z11=Zin with Port 2 open. Therefore I just need to assume Zload=inf at Port 2, and then calculate the input impedance at the left end of the right transmission line, and then move step by step to the left, and the last step should be calculating Zin at Port 1 for the left transmission line.
But how do I calculate Z21=V2/I1 (I2=0)? Should Ia/Ib=R/Za? (where Ia+Ib=I1.) Then does V2=Ib*R-Ia*r? (I guess there is no voltage drop along a transmission line?)
Am I thinking correctly? Any suggestion would be very much appreciated!