Antenna group delay- HFSS calculation

[olza]

Hello,

how to calculate antenna group delay. As I know the group delay is derivation of S21 phase (hence two antennas are necessary).
But in HFSS it is possible to calculate group delay directly from simulation with single antenna, do HFSS include second antenna?

If I measure group delay on network analyzer the result from S11 phase derivation looks similar as that from HFSS and measured S21 phase derivation very different.

Thanks.

 

[Higgler]

If you're measuring S21 for group delay, you should use two identical antennas in the measurement inside a good antenna chamber. Then, divide the delay in half. Each antenna contributes.

I assume you're making a UWB antenna and need to maintain good pulse shape? Or maybe a moderately high bandwidth/narrow pulse radar application.
kch

 

[olza]

Hello,

it is UWB antenna.
But has the group delay of S11 some relevance? If not why it seems like HFSS would calculate the group delay from S11?

Best regards!