far field by HFSS

Can you tell me how i can export far field at rectangular plan situated at z=1m from a horn antenna.
regards.

hi.
you should know that the dimensions of simulated radiation box must be greater than dimensions of your antenna in order 3 or greater.

sorry to disagree , a_aziz

the dimensions of radiation box must not be greater than dimensions of antenna in order 3 or greater necessarily . in this case you can draw a radiation box with only one meter height and compute E & H field on the top plane of it .

sorry to disagree, aboozar.hamidipoor...

The size is radiation box is the bigger the better, as long as you have the necessary computing resource to handle it.

1meter from the antenna might not be far engough such that the field can be considered as "Far Field".

usually, the radiation box refers to the place where radiation boundary is applied. The radiation boundary might be artificial and/or even non-physical (such as close to the PML). So one needs to be mindful that the field computed on the surface of radiation box might not be the physical field (as radiated by the antenna).

I agree with a_aziz and loucy. Simulating a half-wave dipole in hfss showed that a radiation boundary distance from the structure has significant influence on the dipole impedance, while not so much on radiation pattern. Anyway, put your rad. boundary as far as possible (2 lambda) to get good results on both...