A planar dipole array antenna with an elliptical lens

We describe a planar antenna structure consisting of two half-wave dipoles, which are backed by a metallic reflector to create an image of two more elements. The array produces rather a wide main beam, and is therefore used with a dielectric lens. The far-field pattern of the dipole liens antenna has cross-pol better than −20 dB, and side lobes below −13 dB over an octave band. The impedance at the feedpoint of the antenna is approximately 70 - j10 Ω at the center of the band.