Analysis and Design of Multilayered Broadband Radar Absorbing Metamaterial Using the 3-D Printing Technology-Based Method

A multilayered and broadband radar absorbing metamaterial (RAMM) with different structures designed in each of the layers was prepared using the selected laser sintering (SLS) method. A powder mixture consisting of nylon and carbonyl iron powder can be solidified by SLS to form any designed shape. The method would be helpful to make metamaterial. The RAMM was designed using Computer Simulation Technology Microwave Studio software to simulate its absorption properties. The reflectivity of the RAMM was calculated using transmission line theory. It was found that the type of designing changed the surface structure of a conventional slab and increased the bandwidth. The theoretical, simulated, and experimental results all showed that the RAMM had reflectivity below −10 dB in the range from 8 to 18 GHz. We thought the RAMM had an impedance-tapered structure. The main loss was found to occur in the central area of the bottom layer, which simply corresponded to the surface layer.