Iterative physical optics method based on efficient occlusion judgment with bounding volume hierarchy technology

This paper builds a binary tree for the target based on the bounding volume hierarchy technology, thereby achieving strict acceleration of the shadow judgment process and reducing the computational complexity from the original O(N3) to O(N2logN). Numerical results show that the proposed method is more efficient than the traditional method. It is verified in multiple examples that the proposed method can complete the convergence of the current. Moreover, the proposed method avoids the error of judging the lit-shadow relationship based on the normal vector, which is beneficial to current iteration and convergence. Compared with the brute force method, the current method can improve the simulation efficiency by 2 orders of magnitude. The proposed method is more suitable for scattering problems in electrically large cavities and complex scenarios.