Development of radar cross section reduction techniques based on the concept of transformation electromagnetics

Reduction of Radar Cross Section (RCS) of objects, such as airplanes and ships, is an important issue in radar and electronic warfare applications. RCS reduction can effectively be achieved by using the coordinate transformation technique which designs a transformation medium around the object. However, the material parameters of such media are anisotropic and spatially-varying, which make their realizations challenging. In this study, an RCS reduction technique is presented, which employs isotropic and physically-realizable dielectric layers coated over the object. The material parameters of these layers are obtained by using the genetic optimization technique in such a way that RCS of the object coated by isotropic dielectric layers mimics the RCS of the object coated by the anisotropic transformation medium that is designed by using the coordinate transformation technique. Simulations are performed by the finite element method.