[!!!multiple ports HFSS]

Hello everybody,

I need to find the combined reflection coefficient of a two port antenna in hfss.Does somebody has a clue on it? The structure is fed simultaneously by two ports. After simulating it somebody can have s11,s22,s21,s12 but these parameters refer to each port when the other is matched. This is not the case. I need S11 Total so....I guess that it is not possible in HFSS, can somebody give some advice on how I can extract these parameters to another software e.g ADS and then what sort of model should I make to find it

Thanks,

asturias