Innovative optimization-based design of UWB planar arrays for grating lobes reduction

UWB planar phased arrays with inter-element spacing greater than half-wavelength suffer from the presence of grating lobes in the radiation pattern. An innovative approach to mitigate this problem, based on the optimization of the array elements positions along the broadside direction (z-direction) is presented. The main innovation of the proposed new design methodology is related to the fact that the positions of the array elements are left unchanged in the xy-plane, thus not affecting the planar dimension of the array aperture. Selected numerical results are shown to validate the proposed methodology.