room simualation in hfss

Hi,

I'm working on an UWB patch antenna, I have performed my structure using hfss but when I realise my structure I find it very different to practice I don't understand the real cause of this difference especially in the lower band so I repeat the simulation with CST to compare and I find that CST give me more better result than hfss and near to the measure. I have simulated the different scenario in hfss (lumped port, wave port with different dimension, design of the SMA connector, interpolate, change of central frequency) but always the same result. I attach the curves comparing this different results and I wait for your help because I can?t understand why hfss give me this difference? What can I do to have the same result?

Thank you,

Best regards,

Hi,

I am wroking on some UWB antenna designs , If you like i can check your hfss file.

please upload your HFSS projects.


regards

What is the kind of UWB antenna in your work? For me may it is a measure problem, I will repeat them in an anechoic room I verified every think in simulation but always the same result. In your simulation, you take a big radiation box? Recently I take it lambda / 4 far away from every direction (lambda correspond to the lower frequency in my studied band).

Best regards;

Added after 1 hours 44 minutes:

I wait for your reply,

Have a good time

For wideband applications CST is much more preferred to HFSS.