A Compact Wide-Scanning Connected-Slot Array in a Standard PCB for Ku/K/Ka-band Applications

We present a compact and cost-effective design of the unit-cell of a connected array of slots operating in Ku-, K- and Ka-band. A two-section hybrid superstrate directly loading the radiating aperture is proposed to achieve wide-angle impedance matching and enhanced cross-polarization discrimination. The first section is an artificial dielectric comprising three stacked subwavelength patch layers, two of which connected by vias, while the second one is an isotropic dielectric slab. This design comprises a reduced number of layers with respect to the state of the art, and enables an easier and robust fabrication of the antenna in a single standard printed circuit board. The simulated active VSWR is lower than 2.2 in a 3:1 bandwidth, within a scan range of +/- 60 degrees in all azimuthal planes. The numerical analysis of semi-infinite arrays with 16 elements proves that they can cover the same band within a field of view of +/- 50 degrees in the principal planes.