An Optically Transparent Broadband Metamaterial Absorber for Passive Radiation Jamming

Ground-based metal targets are highly visible in passive microwave remote sensing (PMRS) due to their low brightness temperature (BT), making them easily detectable. However, existing passive jamming techniques face limitations such as low effectiveness and technical complexity, highlighting the need for more efficient solutions. This article proposes a passive radiation jamming principle based on metamaterial absorber, elucidating the feasibility of passive radiation jamming against PMRS. A cross square ring staggered rectangular absorber (CSRSRA) with a fourfold symmetric multilayer composite structure is designed to achieve high absorptivity and broadband absorption. Theoretical analysis and simulations demonstrate that the CSRSRA effectively absorbs radiation from ground-based metal targets, ensuring that the detected BT closely matches that of the surrounding environment. This consistency effectively jams the target’s visibility in PMRS. The experimental results confirm the high absorption performance of the CSRSRA, while field experiments further validate its feasibility in jamming the BT of ground-based targets. The results demonstrate that the CSRSRA provides an efficient and practical approach for passive radiation jamming against PMRS, enhancing target concealment while significantly reducing technical complexity.