Conical log spiral modelling

Does anybody knows hot to model a conical log spiral in FEKO or HFSS.
I can model an spiral and an helix but not a log-spiral. How it is possible to generate the log-spiral on a conical surface in the modeller?

Please help me.

Thanks,

Beetro

I would use the equation based plotting feature in HFSS. I have seen conical spirals in their sample problem sets. You might just contact the tech support folks and ask them what they can provide.