Wideband Absorber With an Electrically Tunable Absorption Window and Its Application in Corner Reflector

Abstract The combination of tunable and static absorption at different frequency bands is urgently desired for radar stealth technology yet still remains a challenge. This study proposes a novel strategy of establishing a tunable absorption window in a wideband absorber. A structural prototype is designed with a tunable layer, a resistive layer, and a reflection backplane. By applying biasing voltage to the tunable layer, the absorption of the absorber can be dynamically controlled at 2–6 GHz. After the integration of the resistive layer, the absorption consistently stabilizes at 6–18 GHz. The measured reflection spectra of three planar specimens align well with the simulated results. A trihedral corner reflector is assembled by the planar specimens. The measured results demonstrate that the monostatic radar cross section (RCS) of the corner reflector can be dynamically controlled within specific angular domains at 2–6 GHz while remaining low at 6–18 GHz. The finding holds a feasible scheme in practical application scenarios, capable of implementing radar jamming operations through dynamical RCS responses while possessing low out‐of‐band RCS properties to reduce the risk of radar detection. It is therefore believed that the strategy holds significant promise for applications in radar stealth technology.