Learning Forum

[忻泠 白]

When I made modifications to a certain size variable in the microstrip line, the real and imaginary parts of the S21 model flipped (or moved half a cycle). When I converted the data to phase and amplitude, its amplitude was the same, but the phase difference was half a cycle. I don't understand the reason behind this. Experts who know the reason can help me analyze it. Thank you very much!

[Faezeh Ladani]

Hi there, 

Are you using waveports? Make sure to fix an integration line so the phase reference is fixed the same in all instances of that parameters. 

 

[忻泠 白]

That's indeed the reason, thank you very much for your answer.????