Sidelobe Level Reduction in Ridged Leaky Waveguide Through Stereolithography

This article presents a single-polarized directive leaky-wave antenna at Ka-band providing low sidelobe level. The considered structure is original and consists in a slotted and ridged waveguide, which is excited by a single mode through a rectangular-to-square transition. By properly modulating the length of the slots and the height of the ridge along the antenna, it is possible to achieve full control over the complex illumination. The additive manufacturing process of stereolithography is used to print the low sidelobe level prototype. Measurements are presented and show nice agreement with full-wave simulations, reaching a sidelobe level of - 15.3 dB at 30 GHz.