Corporate-Fed Planar 60-GHz Slot Array Made of Three Unconnected Metal Layers Using AMC Pin Surface for the Gap Waveguide

This letter presents the design of a high-efficiency corporate-fed 8 ×8-slot array antenna in the 60 GHz band. The antenna is built using three unconnected metal layers based on artificial magnetic conductor (AMC) in gap waveguide technology. A 2 ×2 cavity-backed slot subarray is designed in a groove gap waveguide cavity. The cavity is fed through a coupling slot from a ridge gap waveguide corporate-feed network in the lower layer. The subarray is numerically optimized in an infinite array environment. The corporate-feed network is realized by a texture of pins and a guiding ridge. There is very good agreement between simulated and measured results. The fabricated antenna shows a relative bandwidth of 14% with input reflection coefficient better than -10 dB and an overall aperture efficiency larger than 65% (i.e., -2 dB) with about 25 dBi realized gain between 56.2 and 65.0 GHz.