helical gps antenna

I am a beginner in microwave field. Now I get a work to simulate GPS (quadrifilar helix) antenna, frequency 1.22/1.55 Ghz by HFSS/MATLAB but don't know how to begin.

Anyone has simulated or designed this kind of antenna? Could you send me your HFSS/MATLAB file? I guess I can learn a lot from your work.

Thanx a million!

E-mail: thangaswaran_03@yahoo.com

Hi,
Now I am working on this subject, also. I have not used HFSS for simulating this antenna, but CST MWS is a proper software.
Do you have any information about effects of substrate on this antenna's pattern? if you have any reference about effects of substrate, I will be thankful if you introduce me.
Thanks

I just found this old post.

Do you happen to have HFSS design on Quadrifilar antenna?

If yo do, could you please send me the file? I would like to check it out.

My email address is skwok_99@yahoo.com

Thanks.