Inverse-Designed Superstrate for Arbitrary Shaped-Beam Radiation Pattern Based on Inverse Scattering Method

By using inverse scattering method, an inverse design for dielectric-type superstrate of antenna is introduced to get the arbitrary shaped-beam radiation pattern in this paper. The desired radiation patterns are taken as the known information to reconstruct the permittivity distribution of the dielectric-type superstrate within a certain region. Based on the desired radiation patterns, the scattering fields in far-zone can be assumed. Therefore, according to the electromagnetic inverse scattering method, the parameters of the dielectric-type superstrate can be reconstructed. To validate the proposed method, for simplicity, three shaped-beams are considered in the two-dimensional (2D) simulation firstly. Then, the reconstructed 2D dielectric-type superstrates are directly extended to three dimensions (3D) for applications. The results by the 2D and 3D simulations are in good agreement with each other. Good shaped-beam radiation patterns are obtained as expected. In addition, from the reconstructed superstrate, it can be concluded that the inverse design method without any prior-knowledge is well beyond the ability of traditional forward design methods. Furthermore, unlike deep learning which requires datasets for training, the proposed method does not have this process, so it is also efficient.