An ultra-wideband and wide-scanning tightly coupled dipole array with low-profile height and lightweight is presented. A novel split ring (SR) printed on planar single-layer printed circuit board is designed and loaded on each element of the proposed array to replace the conventional wide-angle impedance matching (WAIM) superstrates, which usually consist of dielectric slabs. Consequently, the array achieves a 7.2: 1 impedance bandwidth (0.3-2.15 GHz) while scanning up to 70 degrees in the E-plane and 45 degrees in the H-plane for active VSWR <3.0. Larger scanning angles of 75 degrees in the E-plane and 60 degrees in the H-plane over the same operating frequency are obtained for a relaxed impedance matching criterion (active VSWR <4.1). In a dual-polarized configuration based on modified SR-loadings, the cross-polarization level in the D-plane maintains below -20 and -15 dB for 45 degrees and 60 degrees scanning, respectively. The total thickness of the dual-polarized array is only 0.47 wavelength at the highest operating frequency. An 8x8 prototype array weighing only 4.3 kg (including an aluminum ground plane of 2.3 kg) was fabricated. The measured results are in good agreement with the simulated results.
展开▼
