What is the meanings of multimode S parameter in HFSS?

[x529]

What is the meaning of S(1:3;2:1)?

Reference Linkbase:
（1）http://blog.csdn.net/weixin_44323997/article/details/118786941
（2）http://www.edatop.com/hfss/1207.html

 

[PlanarMetamaterials]

If you excite one mode incident on a port (mode 1 incident on port 2, in your example), then the multimodal scattering parameters yield how much power (relatively) of a given mode is absorbed by any other port (mode 3 on port 1, in your example).