Metallic Dual-Polarized Cylindrical Conformal Phased Array Based on Magnetoelectric Dipoles

In this paper, a metallic magnetoelectric (ME) dipole-based cylindrical conformal dual-polarized phased array (DPPA) with low gain fluctuation is presented. The ME dipole element, which exhibits single-polarized radiation performance, is excited by a coaxial-to-dual-ridge waveguide (DRW) transformer to reduce the size to satisfy the space requirement of a phased array. In addition, two rectangular columns are further added to both sides of the ME dipole element to broaden the beamwidth by regulating the E-field distribution on the radiating aperture. Isolation enhancement methods, including eliminating the shared structure and etching the cross-shaped groove on each rectangular column, are implemented to mitigate the deterioration of the active element pattern caused by the mutual coupling between elements in the planar phased array layout. Subsequently, the influence of cylindrical radius on both ME dipole elements and phased array layout is analyzed. A 6× 6-element cylindrical conformal DPPA operating in Ku-band is implemented by arranging the ME dipole elements orthogonally. Experimental results demonstrate that the cylindrical conformal DPPA supports over ±60° beam scanning coverage in the E- and H-planes across the frequency range of 12-15 GHz. During the beam scanning, the gain fluctuation is less than 3.5 dB.