RADC-TR-81-45, IN-HOUSE REPORT: AUGMENTED ELECTRIC AND MAGNETIC-FIELD INTEGRAL EQUATIONS (MAR-1981)

RADC-TR-81-45, IN-HOUSE REPORT: AUGMENTED ELECTRIC AND MAGNETIC-FIELD INTEGRAL EQUATIONS (MAR-1981)., Augmented electric and magnetic-field integral equations, which preserve the basic simplicity, solution capability, and pure electric and magnetic-field character of the original integral equations, are introduced to eliminate the spurious resonances from the exterior solution of the original integral equations. The exact dependence of the original and augmented integral equations on the geometry of the principal area (self patch) which excludes the singularity of their kernels is also determined; and alternate forms of the integral equations are provided that avoid integrals dependent upon the geometry of the principal area. Numerical results obtained for scattering from the perfectly conducting cube, sphere, and infinite circular cylinder confirm the theoretically predicted result that the augmented integral equations eliminate the spurious resonances for all perfectly conducting scatterers except the sphere.