Problem with patch antenna design

[abhishek]

Re: patch antenna design

hi,

i am designing a patch antenna for a substrate that is just 2 mils thick.
i have used the patch antenna design procedure given in balanis. I am using FEKO for antenna simulation and the antenna is probe fed. But the S11 that i get is -3db, which is pretty high for an antenna. can anyone tell me how to cirumvent the problem? thankyou in advance

abhishek

Added after 3 minutes:

hi,

i am extremely sorry for the error. I mean patch antenna and not a fix antenna.

abhishek

Added after 4 minutes:

patch antenna

Added after 2 hours 4 minutes:

I am trying to type P_A_T_C_H antenna. but it is posting it as fix antenna. i dont know why? may be a modertor can look into that.

abhishek

 

[vfone]

Re: patch antenna design

To design a p@tch antenna on a substrate 2 mils thick is a very big challenge.

 

[redsun]

fix antenna design

the poor impedance matching maybe due to the poor radiation performance, the poor radiation performance maybe due to the too small height of the substrate. you can try to adjust the feeding point to improve S11.

 

[leony]

Re: patch antenna design

I'm working on the same project.The problem is how can I calculate the coaxial probe feed radius? If i find the exact feed coordinates, will the radius of probe feed influence on the impedance matching? I am also simulating my desing with CST MWS.It models the probe feed with a outer and an inner radius cylinder.But I dont know how the values are calculated.

 

[flatulent]

Re: patch antenna design

For a fixed use, your antenna has fewer restrictions than a portable one. I would suggest that you use much thicker dielectric including foam types with mostly air. This will give you much higher efficiency and also wider bandwidth which will reduce the bad effects of manufacturing tolerances.