Optimum Spatial Arrangement of Array Elements for Suppression of Grating-Lobes of Radar Cross Section

A new method to optimize the radar cross section (RCS) for array antennas is presented. A previous work has reported that the RCS of an array is the product of the array RCS factor multiplying the element RCS factor. In this method, the strong scattering from an equally spaced array can be considerably reduced at some certain directions by optimizing the array RCS factor. With the proposed method, the optimized array will scatter waves at a much lower level against prescribed incident directions. In order to illustrate the validation of the proposed method, a planar dipole array and a linear array with bowtie antenna elements are designed and optimized by the proposed method. The numerical and simulated results show that the RCS pattern of equally spaced array generally has some grating-lobes at some certain directions. Hence, the proposed method is applied to suppress these grating-lobes to design a low RCS array. The algorithmically optimized and simulated results validate that the proposed method can help to suppress these grating-lobes.