question about CST MWS mesh grid and source,please help me!

[Players]

meshgrid explained

first,a problem about mesh grid density control.I am really confused with 'lines per wavelength','lower mesh limit' and 'mesh line ratio limit'. What is the relation between them and how to set up these values correct?

second,Is there any special limit on the frequency range ?Such as start frequency (from zero Hz is right?),ratio of the max frequency to the min frequency? A thin wire dipole antenna with frequency range 0-10GHz got 140Ohm at the first resonant point whose ttheoretical value is around 73Ohm.

Thank you very much!

 

[shameemkabir]

Re: question about CST MWS mesh grid and source,please help

Hi!

I guess it is better to use the templates from CST to design your structure which are already optimized. However, sometimes it is needed to do some manual meshing. In that case it is better to know about the terms you are confused about. Would you please take a look at this attachment where these terms are explained!

There is no limit for frequency range. if you want to select 0.5 to 4 Ghz, it is better to use from 0 to 4. Do you really need such a large frequency range for your dipole antenna (0-10 GHz)? If you know the resonant frequency, take the frequency range where the resonant frequency is almost at the middle of the range. And for better results, use smaller difference between max and min frequency.

 

[Players]

Re: question about CST MWS mesh grid and source,please help

Thanks a lot ,shameemkabir.What you said is very important and useful to me .
Today I test again and found that the results will be incorrect if the frequency range is too large.

 

[loucy]

Re: question about CST MWS mesh grid and source,please help

Note that for certain problems, the lower limit of the desired frequency range does affect the simulation. For example it might take longer to reach the steady state because the period at low frequency is longer. So it is not always better to start with 0hz. Another point to note is that MWS is not solving the static Maxwell's equation exactly. The result at 0hz is obtained by some extrapolation scheme.