Low-Sidelobe Flat Panel Array Fed by a 3D-Printed Half-Mode Gap Waveguide Amplitude-Tapering Network

Abstract

This article presents the design and evaluation of an 8×8 Ka-band low-sidelobe slot array antenna using gap waveguide technology. The slot array is fed by a single-layer amplitude-tapering network implemented in half-mode groove gap waveguide, resulting in a low-profile, low-sidelobe antenna. The simplicity of the proposed feeding network, composed of a novel design of asymmetrical dividers, enables precise fabrication using cost-effective additive techniques. Experimental results demonstrate a significant reduction in sidelobe levels compared to traditional uniform arrays, with a radiation efficiency exceeding 84%. This design, featuring simple and robust asymmetrical splitters, is well-suited for applications requiring high gain and low interference. INDEX TERMS Antenna arrays, Bed of nails, Gap waveguide, Half-mode waveguide, Ka-band, Low side lobe, Taylor distribution, SATCOM.