how to use CST3.4 to simulate a broadside couple line?

Anyone there has experience in simulate a broadside microstrip line,the two output port are on the same plane,so if you choose mutiple pin port set ,the result sames not correct,for me,the S21 is positive.who can help me?

Needbias,
please can you upload your structure (without results due to space), we try to help you!
Eirp

My project has no error,I think.It may due to fault of software.Expect CST4 can be better.Now I use HFSS,result sames good.
however,Thx.

Hi, Needbias!
It's is very strange, because I've simulated very complex structures with no problems. Try to use CST4 and read "Advanced Topics" manual (included in install), maybe you need to use full deembeding feature. It must work!
Best regards,
Eirp

I understand.
I had such problem's with CST and solve them only after much addition mesh cells.
I think that in CST is not very good automeshing. Many problem your need to solve by hands and head :) .
In HFSS the mesh's refinement is the better.

I understand.
I had such problem's with CST and solve them only after much addition mesh cells.
I think that in CST is not very good automeshing. Many problem your need to solve by hands and head :) .
In HFSS the mesh's refinement is the better.