Converting S-Parameters to Complex Impedance - RF Cafe Forums

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Post subject: Converting S-Parameters to Complex Impedance

Posted: Wed Sep 15, 2010 4:46 pm

Lieutenant

Joined: Wed Jun 23, 2004 8:44 am
Posts: 1

Hi people. I am looking for the equations for converting s-parameter data to complex impedances. Does anyone know where to find that?

SunshineDesign

Post subject: Re: Converting S-Parameters to Complex Impedance

Posted: Sat Oct 09, 2010 8:29 pm

Colonel

Joined: Sat Nov 08, 2008 11:35 pm
Posts: 30
Location: Ramona, CA

I believe what you are looking for

Zin=Zo((1+S11)/(1-S11))

Zin being the complex impedance and Zo the measurement reference impedance (50 Ohm usually)
S11 being the complex voltage reflection coefficient.

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Posted 11/12/2012

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