Amotech GPS antenna implementation problem in FEKO

Hi all,

I created the following pin fed circularly polarized patch antenna in FEKO to observe its characteristics.

http://www.amotech.co.kr/__Data/_upl...0(Rev%200).pdf

However, it always reflects the whole input signal(S11=1). I am suspecting of my wrong implementation of ground plane described in the datasheet. Relative epsilon is also not described in the datasheet. I am using a line to represent the pin between antenna patch and ground. Line is between upper patch and bottom ground of the ground plane. I am not sure whether both sides of the ground plane is covered with conductor.

Any help is greatly appreciated. I can upload feko file upon request.

I want to have a look at the feko file you have created.

I have solved the problem with the correct determination of the permittivity, which is 20. The next problem is I have to create an array composed of 4-5 antennas of this type, which has to be able to radiate two seperate patterns which are normal mode and anti-jam mode, with appropriate switching of the antennas. We except a beamwidth in normal mode similar to standalone patch antenna. Highest directivity as possible is expected in anti-jam mode.

Please help I am stuck!