Two-Level Tabulated Interaction Method for Electromagnetic Scattering From Lossy Irregular Terrain Profiles Incorporating Back Scattering

An efficient method is proposed for computing electromagnetic wave propagation over lossy terrain profiles using a coupled surface integral equation formulation. The proposed method uses a set of basis functions, which can produce a linear system with much fewer unknowns than that created using pulse basis functions. In addition, the matrix entries can be computed very rapidly using precomputed tabulated values. The method improves upon the original tabulated interaction method (TIM) by extending it to lossy profiles, allowing for back-scatter and by introducing increased accuracy for near-field interactions. The complexity and numerical analysis demonstrates that the proposed method has an extremely low computational complexity and storage requirement. Moreover, the accuracy of the proposed method is demonstrated by comparing the pathloss against numerically precise solutions and measured data.