A Flexible and Efficient Method for the Analysis of Electromagnetic Scattering by Inhomogeneous Objects with Honeycomb Structures

We present in this letter an efficient numerical method for the analysis of electromagnetic scattering by inhomogeneous objects with arbitrarily oriented honeycomb radar absorbing structures. In this method, each cellular honeycomb structure is first homogenized as a diagonal anisotropic medium in local coordinate system by using a new hybrid Hashin-Shtrikman and Mori-Tanaka formula. Then, a Euler rotation matrix is employed for describing a honeycomb structure with arbitrary orientation in a global coordinate system by transforming a diagonal tensor into a general 3 × 3 tensor. Finally, the object with homogenized honeycomb structures are simulated by using the nonconformal domain decomposition finite element-boundary integral-multilevel fast multipole algorithm. Numerical examples are presented to demonstrate the accuracy, efficiency and capability of the proposed algorithm, including the scattering by a typical sandwich panel with honeycomb core, and a complicated fighter model which includes antenna array, dielectric radome and radar-absorbing honeycomb structure.