Abstract

A stacked array of two groove gap leaky wave antennas (LWAs) is proposed for synthesizing broad-beam (or flat-top) radiation patterns. Each LWA is made with full control of the radiation angle and aperture field distribution because of the control of the complex wavenumber of the leaky mode. In addition, both LWAs exhibit sidelobe levels (SLLs) better than -20 dB and 90% radiation efficiency. A power splitter inspired by a groove gap waveguide (GGWG) E-plane riblet coupler is utilized to obtain a one-port network. In this device, the matching loads are not needed because of the antennas' high efficiency and the coupler's directivity. The design of a single-layer LWA based on the design of a diverging beam with a real focus for flat-top pattern synthesis is also shown, and the characteristics of both techniques are compared. The designed array of stacked antennas has been manufactured and measured, and the obtained results show a broad-beam with high angular selectivity and almost constant gain across the designed angular region.