Fast RCS prediction of electrically large targets coated with radar absorbing materials

A method for a fast prediction of the Radar Cross Section (RCS) reduction of large scattering objects coated with radar absorbing materials is presented. The proposed technique is based on the identification of the dominant hotspots of the target from an Inverse Synthetic Aperture Radar (ISAR) image generated over an azimuthal angle of 360°. This ISAR image is the result of the superposition of multiple ISAR images obtained by electromagnetic simulations based on a GO-PO method of the metallic target (without radar absorbing materials). The lowered RCS of the target covered with radar absorbing materials is estimated by a proper attenuation of the hotspots treated with radar absorbing materials in the single ISAR images. The proposed method is applied to some test cases, i.e. a rocket and a ship analysed at the central frequency of 20 GHz.