Cloaking design for arbitrarily shape objects based on characteristic mode method

In the framework of characteristic mode method (CMM) we develop a theoretical approach for achieving invisibility and illusion of three-dimensional arbitrary-shaped objects. Starting from rigorous electromagnetic theory, electromagnetic wave interaction with arbitrarily shape scatterers is modelled by discrete-dipole approximation (DDA) method. By exploiting the characteristic mode analysis, it is theoretically shown that scattered field is tightly related to generalized eigenvalues of the matrix in the DDA method. A theoretical formulation for designing thin homogeneous cover is derived to achieve invisibility and illusion image of the irregularly shaped objects. It is demonstrated by numerical simulations that the proposed cloaking design provides a significant scattering reduction and optimal illusion performance. (C) 2017 Optical Society of America under the terms of the OSA Open Access Publishing Agreement