Printed Reduced Graphene Oxide based Broadband Radar Absorber with Hybrid absorption

A thin split ring resonator (SRR) structure with different SRR orientations is designed and simulated in this paper for X band and Ku band radar cross section (RCS) reduction. The chessboard structure was consisted by two types of SRR arrays with opposite reflection phases, where reflected incident waves from both SRR arrays are cancelled by themselves. For better absorption performance, SRRs are printed by reduced graphene oxide (rGO) rather than traditional metallic materials. The sheet resistance of SRRs have been optimized in this paper for better matching with free space, which enhanced the absorption of incident wave, also increased the bandwidth significantly. Both of the unit cell SRR, $4 \times 4$ and $8 \times 8$ chessboard structures are analyzed quantitatively.