Wideband Reconfigurable Frequency Selective Rasorber With Absorption Enhanced Fusion Bias Network

Reconfigurable frequency selective rasorber (FSR) has garnered significant attention due to its in-band stealth ability for antennas. However, the robustness of stealth performance is constrained by wide passband and bias network. In this work, a wideband reconfigurable FSR with robust absorption is pro-posed by incorporating an absorption enhanced fusion bias (AEFB) network. Through the integration of resonances, the AEFB modifies the capacitive or inductive impedance characteristics of traditional bias into a more adaptable impedance, thereby aligning with and extending the absorption spectrum. The AEFB is symmetrically and orthogonally positioned with respect to the lossy layer to ensure polarization-independent operation. The AEFB-enhanced FSR is realized through a bilayer structure, exhibiting a passband spanning 3.81–4.29GHz (11.8%) and an absorption bandwidth exceeding 110%, achieved with a thickness of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.107\lambda _{L}$</tex-math> </inline-formula>. The fabricated reconfigurable FSR integrated with AEFB exhibits effective rasorber, absorber, and polarization selection functionalities, thereby validating the design principles. This work opens new avenues for robust absorption and electromagnetic wave (EMW) manipulation through reconfigurable FSR.