Rectagular patch antenna transmission line model

[vfurlan]

Hi everbody.
I need a transmission line model for a rectangular patch antenna feed with a microstrip line distant from the center line (figure: patch).
I know the transmission line model for a centerline feed patch antenna (figure:transm_line_model) but I'm not sure if it is the same for not centerline feed antenna.
Please help
Thanks

 

[Azulykit]

Off center feeds are often used to create circular polarized radiation. The idea is to excite orthogonal modes in the patch.

 

[vfurlan]

Yes, but what about transmission line model?