Export PCB design from Altium to CST Microwave Studio

I have designed a PCB for ceramic chip antenna test ( its a copper pour ground plane with an SMA port connection and solder pins for placing chip antenna on it).
I wanted to simulate its effect on the radiation pattern of antenna in CST Microwave Studio. I have made a model of chip antenna in CST MWS but.... Is there a way that I can export this PCB design ( made in Altium Protel) to CST Microwave studio and simulate it? SO that I dont have to draw the ground plane all over again?

What file formats are available for export from Protel? .SAT would work if it's available.

.SAT is not, there is .DXF but that is 2D
Here are the import/ export format both the software accept.
http://wiki.altium.com/display/ADOH/...ortFileFormats
and for CST http://www.cst.com/Content/Products/MWS/ImpExp.aspx , The description of CST PCB Studio does say that it accepts Altium files but my educational license does not permit access to PCB studio , my program crashes !
Please help

try the .stp or step format. looks like it's on the export list for altium and on the import list for cst.