Ansoft HFSS: how to get the Scattering cross section(SCS) and ACS using HFSS.

Recently, I have been using HFSS to simulate some properties of the nano particles,the excitation is plane wave ,now ,I wanna know whether can we use the radiated power to calculate the scattering cross section (SCS)or not?(I have used it to calculate the SCS,but the result seems not correct.)In addition ,how to get Absorption Cross Section or some data refered to ACS? or some advice?
Thanks!