Analysis of antennas with low conductors

Hi all,

I have been trying to analyse antennas with low conductors,
especially microstrip antennas. I used microwave office and feko
but the results were almost the same with the ones of
perfect conductors.

Since the conductivity effects current distribution a lot
i was expecting such a different pattern from the simulations.

If anyone has an idea for the topic, i will appreciate for hearing.

thanks and regards,

erdem

What exactly do you mean by "low conductivity"?

For very lossy metals (sigma > 1e5), the antenna pattern shape should remain the same, but with a significant decrease in gain. The current distribution on a patch resonance is similar for a low loss patch and a high loss patch. Hence, both patches produce similar pattern shapes. The high loss reduces edge effects and corner effects, but the pattern is dominated by shape of the current at resonance which is relatively uneffected by the loss.

Since loss also slows the wave, you will also see the resonant frequency shift lower.

Wiley, thank you very much for your response. I appreciate it.

I am working around sigma <1e4

I think pretty much the same way you do but my suspicion is ithat with very lossy
conductor we wont have currents in edges, or far points from the source point right?
So our current is mostly around the source and our radiator will behave as a smaller one.
I expect the radiation to change a lot. But I am not sure, and In this case it is not easy
to come out with a relativity for radiator size and conductivity.

I couldn't find any experiment on using low conductors. If you have any source or
documents, I will really appreciate if you could share it.

regards,

Erdem