High-Gain 60-GHz High-Order Mode Patch Antenna Array Based on Single-Layer Ridge Gap Waveguide

In this letter, a high-gain high-order mode patch antenna array based on a single-layer ridge gap waveguide (RGW) is proposed for 60-GHz applications. The antenna consists of a substrate printed with patches and a single-layer RGW feeding structure. For the patch element, the modified TM30 mode is utilized as the radiation mode. The increased patch sizes and inter-element spacing not only contribute to a high gain but also provide an enlarged area for the design of the single-layer RGW network. As a result, this leads to lower complexity in the feeding network and potentially decreases the fabrication tolerance and cost. Finally, an 8×8 high-order mode patch array prototype is fabricated and tested. The measured results illustrate that the -10 dB bandwidth is 14.9%, covering from 56.5 GHz to 65.6 GHz. The measured gain within the operating band is higher than 29.3 dBi and the peak gain achieves 30.1 dBi. Meanwhile, the array obtains a high aperture efficiency of better than 71%.