I simulated an antenna in a paper by the HFSS. The efficiency i obtained in is the one the first graph, the efficiency of the paper is the one in the second graph. Can i compare these graph together given they are in different scales?
you have simulated radiation efficiency whereas the paper has total efficiency. CST will give you both total and radiation efficiency. im not familiar with HFSS. get total efficiency plot instead of radiation efficiency which will be comparable to the paper you have mentioned.