High gain millimeter wave leaky wave antennas with low side lobe level of the radiation pattern

Abstract

Two linearly polarized millimeter wave planar leaky wave antennas designed for broadside radiation at 61 GHz with high gain and low sidelobes of radiation patterns are presented. Both antennas have a center-fed single-layer structure composed of two one-dimensional periodic symmetric arrays of metal strips of variable width on a grounded dielectric waveguide, but with different excitation devices for the dielectric waveguide, represented by a microstrip combline and a waveguide-fed linear substrate integrated slotted waveguide array. The antennas exhibit low return loss, antenna gain 26-27 dBi and radiation pattern sidelobe level in both E- and H-planes, not exceeding −20 dB. The antennas may be used, for example, in security sensors.