Modal analysis of loaded N-port scatterers

An N -port loaded scatter is one having N ports to which lumped impedance loads or a load network is connected. Methods are given to determine the characteristic modes of a loaded scatterer and for using them in a modal solution for electromagnetic scattering. A procedure is also given for resonating any given real port current, which makes that current the dominant mode of the loaded scatterer. The theory is formulated both in terms of open-circuit and short-circuit network parameters. A number of numerical examples are given for a wire triangle to illustrate the general theory. Computer programs are available for all procedures discussed.