Fast solution of mixed dielectric/conducting scattering problem using volume-surface adaptive integral method

This paper presents the adaptive integral method utilized to solve scattering problems of mixed dielectric and conducting objects using volume-surface integral equation. The scattering problem is formulated using volume integral equation and surface integral equation for dielectric material object and conducting object, respectively. The combined field integral equation is formulated to treat closed conducting surfaces. The method of moments is applied to discretize the integral equations. The resultant matrix system is solved by an iterative solver where the adaptive integral method is employed to accelerate the matrix-vector multiplication. The block diagonal preconditioner is implemented to further accelerate the convergence of the present solution. Numerical results are presented to demonstrate the accuracy and efficiency of the technique.