What are the possible DGS shapes in microstrip patch antennas?

does anybody know any shape for DGS in microstrip patch antennas except dumbbell?
does any body have any kind of suggestion?

hi,

there maybe you will find something,
https://www.edaboard.com/viewtopic.php?p=874891#874891


but in fact there are many different shapes, I'm doing fractal DGS so I had to find all shapes what was made before (or try to find),
not including fractals I found about 10 different conceptions in IEEE

Have you tried to use Fractal shapes?

I'm interested in DGS, but I don't want to have a back radiation. Have you observed the back radiation caused by the radiation of DGS shape?

regards,