Error in the convergence of antenna in hfss

[ings]

Hello,
i hae a prblem in my smulation for antenna monopole
when i run this prject this anayse is ok and run is about 2 hours and fnaly he dsplay me error in cnvergence
what is the solution please

 

[PlanarMetamaterials]

The solution to your problem, like most problems in life, will depend on what the error is.

 

[flanello]

Do you get some results? Do the results looks reasonable?
How many adaptive passes does your simulation do?

 

[ings]

in the first i dnt have result but when i m delete the groud i have obtain the result ( because i have a stucture diferent )
i have a question about the dimension of antenna monopole please
if the frequency = 2.4Ghz so the length of antena L=c/(2*f)
so the dimension of ground andd the cylinder of the port how can i caluculate them?

- - - Updated - - -

i have 15 pass

 

[SvenB]

in the first i dnt have result but when i m delete the groud i have obtain the result ( because i have a stucture diferent )
i have a question about the dimension of antenna monopole please
if the frequency = 2.4Ghz so the length of antena L=c/(2*f)
so the dimension of ground andd the cylinder of the port how can i caluculate them?

- - - Updated - - -

i have 15 pass

Firstly, the length of a monopole antenna should be a quarter wavelength (i.e. L=c/(4*f)). That's why, when you remove the ground-plane, you have better results as in that case it works as a dipole antenna at 2.4 GHz, with ground-plane the antenna is optimized for 1.2 GHz (you will see this resonance in your S-parameters).

Secondly, the dimension of the ground plane will alter your radiation pattern, it should at least be a few wavelengths in both dimensions to reduce this "skewing" of the pattern. Check with far-field simulations if the pattern is ok, otherwise increase the ground plane size as much as is feasible.