qha feed

Has someone a model of any QHA in HFSS?
My main problem is understand how to feed the antenna in order to produce a phase difference of 90 degrees when I move from one wire to the next.
I attached my model in HFSS, but it has a big problem the coax cables that I used to feed the helices produce a radiation that distorts the radiation patterns

hi my friend!
i have simulated QHA but i didn't have this problem!
can you send me your file to "ordibehesht.yep@gmail.com"?
good luck

hi rocco
u hfss simulation has too many problem u antenna size in range of centimeter and i want ask u whats u antenna frequency ?
i repair many of u file fault by i dont understand u antenna frequency and i think u maybe fault in scale?