hai.....

I was trying to model circular patch antenna (and its variatios) return loss,impedance and vswr characteristics with FEKO. I fed it with inset feed method and used the formula to compute the impedance match of 50ohms on antenna. The simulation worked perfectly. But the dB(S11) parameter seems to be shifted and at that time impedance and vswr is correct and if the return loss is correct at that time impedance and vswr is seems to be high. Now I try to feed the same structure with changing meshing but nothing work with this. I used these values, radius=38,inset width=1.5mm,and insetfeed is 3.5 with epsr=4.5. I m using microstip port at the end of feed. I think there is some problem in parameters which i have used. Can anybody explain how to use microstrip properly to feed patch at inset location. i used the way it is described here in the document. I m not sure why it wasnot working properly... Please solve my problem at ur earliest... Thanks....

make the thing more clear