Design of a planar ultra-wideband modular array antenna

This article proposes a planar ultra-wideband modular array antenna with a low profile, wide bandwidth, and wide scanning angle. The antenna’s basic structure includes a feed structure consisting of microstrip impedance transformer and metal cylinders, a radiating structure composed of dipole units and rectangular patches, and a wide-angle matching layer placed on top. To move the common-mode resonance out of the band, metal plates are added on both sides of the unit. The results show that the antenna achieves a 6.1:1 bandwidth at broadside, a 5.6:1 bandwidth scanning to 60° in the E-plane and a 5.1:1 bandwidth scanning to 45° in the H-plane, with a profile of $\mathbf{0. 1 0 6} \lambda_{\text {low }}$.