Design of ultra-wideband absorbing metasurface driven by genetic algorithm via gradient impedance matching

To address the urgent demand for broadband electromagnetic wave absorption in modern devices, this study proposes an innovative design method for ultra-wideband absorbing metasurfaces, based on the impedance matching principle and driven by a genetic algorithm. Targeting the requirement of over 90% electromagnetic wave energy absorption across the entire L-Ku (1-18 GHz) band, the core concept involves intelligently optimizing the spatial arrangement of discrete resistive film patterns within a multi-layer structure using GA to achieve fine-tuned impedance matching over a broad bandwidth. This method overcomes the limitations of traditional design approaches, which rely heavily on experience and struggle to efficiently solve broadband matching problems. Notably, the absorber achieves a thickness reaching 90% of Rozanov's theoretical limit thickness while exhibiting low areal density, demonstrating significant application potential in areas such as microwave stealth and electromagnetic compatibility.