[SOLVED] How to test and fabricate an FSS

[muhammad idrees]

Hi all;

I have done simulation of Frequency Selective Surface design successfully. But the problem is to fabricate and test an Frequency Selective Surface. tell me the way how to test and fabricate kindly help me regarding this.

Secondly how many FSS unit cells are required to fabricate and testing at a time? Means an array of FSS unit cells or Single unit cell?

Best regards

 

[rrumpf]

How many unit cells you need depends on the physics your FSS is based on. If your FSS is based on element resonance, you will only need 5 to 10. If it is based on array resonance, you could need dozens to 100's.

Hard to say how to fabricate without knowing what your FSS looks like, but most are fabricated using the same processes as standard printed circuit boards. When you test it, you will need two standard gain horn antennas and a network analyzer to measure reflection and transmission. Setup the two horns at some distance away from each other with nothing between them. Calibrate this to be 100% transmission. Now put your FSS a foot or so in front of the receiving horn and you will be measuring transmission through the FSS.

 

[muhammad idrees]

How many unit cells you need depends on the physics your FSS is based on. If your FSS is based on element resonance, you will only need 5 to 10. If it is based on array resonance, you could need dozens to 100's.

Hard to say how to fabricate without knowing what your FSS looks like, but most are fabricated using the same processes as standard printed circuit boards. When you test it, you will need two standard gain horn antennas and a network analyzer to measure reflection and transmission. Setup the two horns at some distance away from each other with nothing between them. Calibrate this to be 100% transmission. Now put your FSS a foot or so in front of the receiving horn and you will be measuring transmission through the FSS.

Thanks rrumpf;

Actually the FSS design i have simulated in HFSS has the dimensions of 25 x 25 mm. It is designed to stop the WiMAX frequency band 3.5 GHz. As per my knowledge we require minimum 10 x10 elements to test and fabricate the design.

But the issue we are facing is the machine used for fabrication can fabricate only A4 size sheet. Due to this reason 8 x 11 FSS unit cells fit in the A4 size sheet.

Kindly tell the way that how we can resolve that issue?

With best regards:

Muhammad Idrees

 

[CG0210794]

Muhammad - You can make multiple sheets and connect them. You need to make sure that when you connect more than one piece that the outer unit cells remain the same size. You could then get a piece of styrofoam and tape/glue the pieces together. Also, rrumpf gave a great way to test the FSS. The only difference is that when you calibrate for 100% transmission you need to place a piece of styrofoam, with no FSS, with the exact same dimensions as the one you are going to use for the back of your FSS.