A low-profile wideband and polarization-insensitive metasurface absorber for X and Ku bands

This work presents the design and performance evaluation of a single-layer broadband metasurface absorber (MSA) for X and Ku bands. The top surface of the MSA consists of an internal gap cross-dipole resonator (IGCR), edge-touching rectangular copper wires (ERCW), and lumped resistors, while the bottom layer is a solid plate, separated by an FR-4 substrate. The proposed MSA exhibits remarkable characteristics, achieving over 90% absorption across a wide microwave band under normal incidence for all polarization angles. Even under oblique incidence, the MSA maintains its performance, delivering over 90% absorption in transverse electric (TE) mode despite variations in the incident angle of up to 40°. Similarly, in transverse magnetic (TM) polarization, the absorber sustains over 90% absorption from 10.30 to 15.78 GHz, accommodating incident angle variations of up to 60°. With its high performance and low-profile nature, the proposed absorber exhibits significant potential for applications such as stealth technology, energy harvesting, and reducing radar cross-section (RCS).