Design of an X-Band Wideband 2 × 2 Waveguide Antenna Array Based on Slotted Spherical Radiators

This paper presents RF design and electromagnetic simulation of an X-band wideband 2 × 2 waveguide antenna array based on slotted spherical radiators. The devised antenna array is composed of four wideband slotted spherical radiators that are deployed in a 2 × 2 array configuration and are fed uniformly through a wideband 1-to-4 waveguide power divider. The power divider is designed with compact size by properly twisting the waveguide arms. The antenna array is tailored in the geometry so that the entire physical model can be prototyped monolithically by employing 3-D printing technology. The simulated result of each single slotted spherical radiator shows directional radiation patterns in a wide relative bandwidth (RBW) of ~40% at X band with a reflection coefficient of <; -10 dB, realized gains as high as 8.2-11.3 dBi, and total efficiencies of mostly >90%. The X-band 2 × 2 slotted spherical array exhibits wideband (~40% RBW) radiation performance from 8.3 to 12.3 GHz with a reflection coefficient of <; -10 dB, realized gains of 12.7-17.2 dBi, and total efficiencies of mostly >90%.