hfss directivity

When I simulated an Biconical antenna in HFSS, the gain is larger than directivity, why? who can give me a answer? thank you!

Hi snowboy
if you compare total gain with total directivity?

I had the same question before but still no anwer.

My first suspicion would be that the model was not sufficiently converged and that the mesh might bee too sparse at the interface to the background. You may need to do some manual seeding to increase the density.