# Antenna with uniform current distribution and 2D structures

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Dear all

First of all i have little experience with EM software and i will be very happy if  you give me some guidelines and support.

1. I am trying to simulate a circular loop antenna but it is necessary  the current distribution to be uniform (constant)Iφ=I0 in order to compare the analytical solution directly with the simulated one. I m trying to insert multiple voltage sources but i cant achieve constant current (phase and amplitude). Do you have any idea or advice how it will be possible;
2. Are there any tutorial or example or advice how to simulate 2D structures in FEKO? I would like to simulate something like the parallel plate WG but i have infinity to z-axis and y-axis. One solution is the PBC; Are the any other method;

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Hello @Theodoros

1. It is difficult to know if constant current is required without knowing more about the specific antenna. You are welcome to attach the .cfx file so that we can check how you have set it up

2. You may also want to have a look at what is possible with the planar Greens function.

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Hi
For a constant current distribution, I would suggest that you try to model it with one or more impressed current sources (they have to be straight lines, so you will have to use a few to approximate the loop). In reality, the current won't be constant, but for a small enough loop, it will be approximately constant. If you are simply trying to model an infinitely small loop, rather use a magnetic dipole source.

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2 hours ago, JIF said:

Hi
For a constant current distribution, I would suggest that you try to model it with one or more impressed current sources (they have to be straight lines, so you will have to use a few to approximate the loop). In reality, the current won't be constant, but for a small enough loop, it will be approximately constant. If you are simply trying to model an infinitely small loop, rather use a magnetic dipole source.

Dear JIF
First of all i would like to thank you for the immediate response.

Until now the small circular loop model is the only solution that i can think. Theoretically speaking the circumference of the loop should be C<0.2λ but in FEKO in order to achieve a good result should be at least C<λ/100. (just for informative purpose).
Do you have any idea how i can simulate 3 Cubes:  1st PEC,Dielectric, 2nd PEC; The structure (PEC, Diel, PEC) should be infinite along z-axis and in addition the second cube should be infinite to z and x-axis.

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Are you talking about 3 cubes in one model? This sounds like a very weird model. For infinite structures there are only two options:

• Periodic boundary conditions (PBC)
• Green's function (planar multilayer substrate)

Both have limitations, so it really depends on what you are trying to model.

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On 10/25/2018 at 2:45 PM, JIF said:

Are you talking about 3 cubes in one model? This sounds like a very weird model. For infinite structures there are only two options:

• Periodic boundary conditions (PBC)
• Green's function (planar multilayer substrate)

Both have limitations, so it really depends on what you are trying to model.

Here is the geometry.
It is very simple but how the infinity should be declared.
I would like to know the near, far field and the reflection coefficient.