S Parameter on HFSS and two modes

[markito86]

Hi,

I have a simple question to do. I have implemented a 4 ports coupler 3dB of 2 rectangular waveguide.
Each port is excited by 2 mode (vertical and horizontal) in order to verify if the coupler is dual mode.
When I create a quickly report, there are a lot of S Parameters defined i.e. S(3:2,4:2) but I don't understand each number what means.

I think the only two modes TE10 and TE01 propagates and so S Parameters for all ports for each mode.
What are all other parameters ?

 

[kspalla]

S(3:2,4:2) means S(3,4) in mode 2 excitation at port 4 to mode 2 response at port 3