ADS Interleaved Arrays with Reconfigurable Polarization

Polarization‐reconfigurable arrays play a fundamental role in radar systems in order to enhance their detection probability and cancel clutters, chaffs, and jammers [1]. In order to reach polarization flexibility, the integration of actively controlled elements in standard array configurations is often employed [2], but the overall system complexity and costs significantly increase [3]. To overcome such limitations, the use of two shared aperture arrays with independent polarizations was proposed in [3] by exploiting an interleaving scheme based on Difference‐Sets (DSs). By combining the field generated by each sub‐array, arbitrary polarizations, low sidelobes, large steering angles, and narrow beamwidths can be reached with a limited complexity of the underlying feeding network. Despite its theoretical and practical advantages, only few planar array geometries can be synthesized because of the limited number of available DS sequences [4]. A different set of binary sequences [called Almost Difference Sets (ADSs)] [5][6] with properties very similar to those of DSs has been recently investigated. Besides their application in code theory [5], ADSs have already shown their effectiveness in synthesizing thinned arrays with low and predictable sidelobes [7][8]. This paper analyzes the properties of polarization‐flexible planar arrays based on ADSs. Numerical simulations are presented and discussed by focusing on the sidelobe level control and the polarization selectivity of the synthesized ADS arrays.