effect of ground on antenna

I have some serious doubts can anybody clarify these pls.
1. effect of metallic ground plane on vivaldi antenna (i made some traveling slot antenna with 120 deg HPBW in both planes but in practical its not behaving as in simulations by HFSS)..kindly put some light on feed SMA connectors and mounting structure

2. seen some papers using wooden planks for support..why? from point of view of phased arrays we require metallic back up structure


Kindly share some material or experience with me as soon a s possible

hey no body can help me on this..spare some time

i'll give u paper and hope that may help u
ok
but i don't know how to upload it
my e-mail is
amgad.salama@gmail.com
send me so i can give it to u
ok

my email is ashutosh.kedar@gmail.com kindly send em the paper and other info if possible