dsign methdology for planar shaped microstrip patch antenna for wimax

I am trying to figure out how to design an ECA-Patch antenna for WIMAX part of a FINAL design project in HFSS. I've designed linearly polarized rectangular patches, and circularly polarized square patches and arrays but never any upper case letter shape.

What is a good starting place to find design methodology. I couldn't find much from Balanis, I've found some IEEE papers, but of course they leave out all the juicy details I want. Any suggestions would be wonderful.
Thanks.

Design Criteria:
3 Ghz-5 Ghz
BW= 8.15%