# Calculating the Inductance and Q of Spiral Inductors - RF Cafe Forums

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mmaassel
 Post subject: Calculating the Inductance and Q of Spiral Inductors Posted: Thu Sep 16, 2010 2:46 pm
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Joined: Mon Apr 10, 2006 12:43 pm

Posts: 25

 Good day.I am working on calculating the inductance and Q of some spiral inductors. These inductors are modeled using Momentum from Agilent. A Momentum example gives the following procedure - (1) Convert the S-Parameters to Z-Parameters using ZM_2p=stoz(s)(2) Convert the 2 port Z-parameters to a 1 port Z-parameters. Agilent states that Port 2 is considered to be grounded. Z_2pTo1p=ZM_2p(1,1)-2*ZM_2p(1,2)+ZM_2p(2,2) Then use the real and imaginary parts to determine the inductance and resistance. The question I have is in step 2. I come up with the equation Z_2pTo1p=ZM_2p(1,1)-(2*ZM_2p(1,2))/(ZM_2p(2,2)) Where did I go wrong?Thank youMichael

Posted  11/12/2012