Difference between S-parameter and S-parameter(AR) in CST

What is the difference between S-parameter and S-parameter(AR) result available in CST? I'm getting different results for those S-parameters,so which one is the correct S-parameter to take?

found the similar issue being discussed at https://www.edaboard.com/thread305317.html

but I couldn't get rid of the ripples, might be caused by nearby port location?

hi

where did you see in cst s-parameter (AR)? in post prossesing ?