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 TM<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">30</sub> mode is utilized as the radiation mode. The increased patch sizes and interelement 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%.