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Design >> RF Design >> Simulate odd mode/even mode impedance of coupler using S param sim
https://designers-guide.org/forum/YaBB.pl?num=1657816854

Message started by vlsi_design on Jul 14^th, 2022, 9:40am

Title: Simulate odd mode/even mode impedance of coupler using S param sim
Post by vlsi_design on Jul 14^th, 2022, 9:40am

Hi, I am designing a coupled line coupler and I want to simulate Zoe and Zoo vs freq. Can I use an ideal balun to provide differential excitation and reduce it to a two port problem and do s param -> ABCD pram and the use sqrt(B/C) to find Zoo. Can I use center tap of the balun to evaluate Zoe similarly?

Title: Re: Simulate odd mode/even mode impedance of coupler using S param sim
Post by Ken Kundert on Jul 14^th, 2022, 10:14pm

I believe that is the correct approach. You will need to think carefully about the needed differential and common mode reference resistances and choose the reference resistances for the ports that drive the differential and common-mode ports of the balun accordingly.

-Ken

Title: Re: Simulate odd mode/even mode impedance of coupler using S param sim
Post by vlsi_design on Jul 24^th, 2022, 6:45pm

Thank you very much Ken. :)