Stealth 2-D Leaky-Wave Antenna Integrating a Radar Absorber

This letter presents a stealth two-dimensional leaky-wave antenna (2D LWA) with integrated radar-absorbing properties. Substrate-integrated image guide (SIIG) is employed to construct the LWA. The use of patch-type radiating elements without direct metal connections allows the antenna to perform in-band beam scanning while also enabling control over its out-of-band reflection properties. To this end, the patches are loaded with a metal-based resistive ink to maintain the reflection and absorption characteristics, ultimately enabling the antenna to combine beam scanning with out-of-band absorption. Moreover, the low-profile, integrated design reduces the spatial requirements for a radar system incorporating a radome. A proof-of-concept prototype is fabricated and measured, which demonstrated frequency-controlled beam scanning from -40° to 0° and a wide absorption bandwidth from 7 to 11 GHz. Owing to its beam-scanning capability, absorbing properties, low profile, and low cost, this LWA is a promising candidate for radar systems requiring stealth, scanning, and detection functionalities.