[SI-LIST] S11 and S21 for PCB trace with different dielectic think

Hi,
 

I am trying to extract the S11 and S21of some PCB traces using one of
the field solver tools. The traces are running on top of a solid ground
plane, and I run the simulation for two different dielectric thickness
settings. In one case, the Zo for the trace is around 50-ohm, and the
other case the Zo is around 80-ohm. The S11 and S21 for the two case is
quite different. The insertion loss S21 is much less and smoother
through out the frequency range in the case of 50-ohm. The reflection
coefficient S11 is also much closer to zero in the case of 50-ohm. 

 

Is it because the port reference is set to 50-ohm for the simulation, so
the result for the 50-ohm case is much better? If so, how can we use the
result if the system is not 50-ohm in the real case?

 

Regards,

 

John 


------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:
http://www.freelists.org/webpage/si-list

For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field


List technical documents are available at:
                http://www.si-list.net

List archives are viewable at:     
                http://www.freelists.org/archives/si-list
or at our remote archives:
                http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
                http://www.qsl.net/wb6tpu

Other related posts: