connecting s matrices

Hello,

the above figure shows the cascade-connection of an ideal 3dB coupler with an arbitrary two port s-matrix.

Normally, i first switch from S to T paramters (transmission parameters), to easily cascade by multiplying.

In the following example we want to connect the 4x4 coupler matrix with the 2x2 two port matrix. It obviously, there is an easy way to do it. The result is also shown in the figure.

thanks for any comment.
elektr0

really, no ideas