Improved surface impedance methods for 2-D and 3-D problems

The surface impedance method is improved for 2-D and 3-D problems by using more accurate values of impedance based on the spatial variation of fields on the surface of conducting regions. This enables problems to be solved by computing only the scalar magnetic potential in air regions. The method has also been extended to thin and to curved media, and the requirements for matrix symmetry are described. The method has been applied to two test problems: the infinitely long cylinder and the hollow sphere in uniform sinusoidal fields. The solutions obtained are about 6% and 4% in error, respectively