Hi everyone,

I am trying to study about S parameters in ADS. I have seen from a file that in the "stoy" function, there is a variable defined in Mea Eqn as follows:

Param_y = stoy(S[1::2,1::2]).

In the schematic, there is an element called "S2P" driven by two ports Port 1 and Port 2. I guess that this is to transform S paramters to Y parameters. But, what does the syntax

S[1::2, 1::2] mean ?

Could someone explain to me please ?

Thank you very much,

DYL

Pancho's link explains what the notation means, but if you want to know a simple way to use the stoy function just use (I think)

stoy(S)

or if you prefer or need z-parameters

stoz(S)

these functions will save the y and z parameter equivalent results for each s-parameter analysis simulation (all ports).

The wildcard and sequence notation would be useful if you are only interested in doing a conversion for some select ports (I think).

I use these functions when I'm interested in calculating the either the series or shunt effective lumped element equivalent resistance, capacitance and/or inductance over frequency.

Hi RFDUDE,

Thank you very much for your explanation.

DYL

Ah, my fault, I mean comparison between S(3::4,3::4) and {{S33,S34},{S43,S44}}, the result should be the same.

DYL

Hi pancho_hideboo,

Thank you very much for your reply. This is my another new knowledge about ADS.

DYL