Import .sNp to Microwave Office - Limit on N ports?

I have an .sNp file exported from HFSS, and I can usually import them into MWO without any problems and use them as sub circuits etc.
However, when I had a larger .sNp file (18 ports) I was not able to import it. It did not even show up in the browser when looking for the files.

Is there a limit to the number of ports in these S-parameter files?

Thanks,
~Nick

Hello Nick,

The touchstone file format for S-parameters has no limitation on number of ports (it supports upto 99 ports)
only your data HEADER format shout match
If the data is real/imaginary and the frequency unit is GHz, the header line is this:
# GHZ S RI R 50.00

If the data is in magnitude dB and phase format, the header line is this:
# GHZ S DB R 50.00

So AWR Microwave Office (MWO) supports above format...

If you still have problems then upload your *.S18P file here....