I want to model an artificial transmission line with L & C. So far I used the following circuit and used the values of L=400 pH and C=0.16 pF so that Z=sqrt(L/C)=50 ohms. So, expected S21 and S31 could have a 3dB or 6dB drop from 1 to 2 and 1 to 3. (power divider).
The gain is lower than 0 dB which I am not worried as of now as I will put some transistors in future (adjust the L values as well) and correct the gain.
But I am worried about the frequency independent behaviour. Well, I see that the input power flows from 1 to 2,3 well from 5-20 GHz. If I change the value of L to 1nH and C to 0.4 pF, then I see that it works at a different range.
During my design with transistors, I can figure out the capacitor parasitics that I would be getting (C_total) per node and then figure out the L depending upon the same formula Z=sqrt(L/C_total). But how can I be sure that the L value which I found works?
Am I missing something?