Unimoment method of solving antenna and scattering problems

It has been shown by this investigator and numerous others [6], [7], [8] that exterior boundary value problems involving localized inhomogeneous media are most conveniently solved using finite difference or finite element techniques together with integral equations or harmonic expansions, which satisfy the radiation conditions. The methods result in large matrices that are partly full and partly sparse; and methods to solve them, such as iteration or banded matrix methods are not very satisfactory. The unimoment method alleviates the difficulties by decoupling exterior problems from the interior boundary value problems. This is done by solving the interior problem many times so that linearly independent solutions are generated. The continuity conditions are then enforced by a linear combination of the independent solutions, which may be done by solving much smaller matrices. Methods of generating solutions of the interior problems are discussed.