On generalizations of the maximum power transfer problem

The necessary conditions for maximum power transfer to the outputs of a multiport are discussed. The condition Z = Z0^*is sufficient. A solution to this problem is not generally unique, because the matrix Z must satisfy the matrix equation Z(Z0+ Z0^*)^-1E0= - Z0(Z0+ Z0^*)^-1E0+ E0. When the power transfer is maximum, only the total power of the equivalent sources is equally divided between the "passive" multiport and the ports.