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I have a composite polymer material with injected conductive particles inside it, making it a not-so-perfect conductor. I have also fabricated a simple dipole antenna using the wires made of the composite, and it is radiating at 2.4GHz without any problems. Checked with a network analyzer.

I have also tried to simulate it using CST microwave simulation software, but since the material is "home-made" and not defined in software material library, I have to define it by myself by specifying the conductance of the material and define it as a "Lossy metal".

For this, I tried to measure the DC resistance of the material and calculated conductance from it, which shows relatively high resistance and therefore low conductance. I also tried to simulate it with the values that I got from the measurement but there was no luck and it acted like a normal dielectric without any radiation.

The material looks resisting in DC but conducting as a 2.4GHz dipole antenna?

Am I doing something wrong? or forgot something? And what should I do to simulate accurately?

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  • \$\begingroup\$ At what frequency did you measure the conductance... DC? Try measuring conductance using a load resistor and a frequency generator. The antenna is a resistor, so you have a resistor divider. Inject the same amplitude at different frequencies and look at the amplitude coming out. Could be that the material seems non-conductive at DC but 80% conductive at higher frequencies. \$\endgroup\$
    – rdtsc
    Commented Mar 11, 2020 at 17:22
  • \$\begingroup\$ 'Lossy metal' probably does not describe your material. If the software can't calculate the conductance at 2.4GHz from its composition then you may have to measure it \$\endgroup\$
    – Bruce Abbott
    Commented Mar 11, 2020 at 17:30
  • \$\begingroup\$ @rdtsc But how can one measure it in a high frequency like 2.4 GHz? cannot simply use resistor divider setup. \$\endgroup\$
    – Anonymous
    Commented Mar 11, 2020 at 20:16
  • \$\begingroup\$ At RF frequencies a Spectrum Analyzer or Vector Network Analyzer would be the tool of choice. \$\endgroup\$
    – rdtsc
    Commented Mar 11, 2020 at 20:36
  • \$\begingroup\$ @rdtsc The main problem is the experiment itself. In RF you cannot pass the signal simply using wires. You should use waveguide forms like coaxials. This is where the real problem occurs when you want to measure conductance of a wire. \$\endgroup\$
    – Anonymous
    Commented Mar 12, 2020 at 18:58

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