simulation of an impedance step, Transistor -> Match Net. - RF Cafe Forums

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ingo
Post subject: simulation of an impedance step, Transistor -> Match Net. Posted: Fri Apr 28, 2006 1:23 pm

Lieutenant

Joined: Fri Apr 28, 2006 1:09 pm
Posts: 1
Hi together,

I wonder how to simulate follwing condition correctly:

I have a Transistor with a connection lead of 12 mm width.
My first matching element has a width of 23mm.
I have a large signal model of the transistor for my simulator (ADS).
Das anyone konw, how to simulate the behaviour correctley?

Transistor -> Microstripline (width 23mm),

or

Transisor -> Impedance Step (12mm -> 23mm) -> Microstip (23mm)

Both simulatons show different results.

Would be happy for the comments from you.

Ingo

Top

IR
Post subject: Posted: Fri Apr 28, 2006 3:43 pm

Site Admin

Joined: Mon Jun 27, 2005 2:02 pm
Posts: 373
Location: Germany
Hello Ingo,

The second option which you mentioned, namely to use an impedance step is the right one. Of course that both simulations show different results, because you have a discontinuity in the impedance if you don't use an impedance step, and therfore you get an impedance mismatch and poor return loss.

_________________
Best regards,

- IR

Posted 11/12/2012