4GHz helical antenna design

i am having problems designing 4GHz helical antenna. I tried tuning it using 7.5 mm clearance but it didn't work so i did it on 1mm and it tunned ok but the E field plot isn't really nice. The fields should be enforcing each other and it should be confined to the helix but no matter what i do, its not working. Please help me out

thanks in advance

i am attaching the file with this post

j Kraus, "Antennas" has extensive information on spirals.

hi i have tried it but it still doesn't work. How much should be the ground clearance for a 4GHz antenna

hi.i can you need to design a semi ground for your antennas.you can design this whit use of kraus "antenna".