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),

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

Both simulatons show different results.

Would be happy for the comments from you.

Ingo

Top

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