Show that in the indefinite scattering matrix given in 1634

Question

Question: Show that in the indefinite scattering matrix given in (1.6.34) the sum of the coefficient of any row is equal to 1 and the sum of the coefficient of any column is equal to 1.

I₁⁺ = I₁^- + I₂^- + I₃^-

Therefore, it follows that

S₁₁ + S₂₁ + S₃₁ = 1

The circuit shown in Fig. P1.23b can be used to show that the sum of the coefficients in any row is equal to 1.