Metamaterial Based Microwave Absorber

Metamaterials are structures with extraordinary properties such as artificial geometry

and negative refraction. In recent years, these materials have been used to improve

the performance of various microwave devices such as antenna, sensor, cloak,

polarization converter with the advantages of easy production. Microwave absorbers

are devices that prevent the transmission and reflection of electromagnetic waves.

With these aspects, they can be used in applications such as reducing the radar crosssectional area and antenna side lobes. Metamaterial absorbers have been realized for

wide bandgap as a complex using materials such as thin films, optically transparent

materials, lumped elements. For less complexity, dielectric substrate and SRR

(spling ring resenator) structures were performed for the millimeter and THz

frequency regions. Therefore, materials such as FR-4, rogers, F4B were chosen as

substrates in the design of metamaterial absorbers. In this study, a metamaterialbased penta band absorber was designed. In the proposed design, FR-4 was chosen

as the substrate, with a thickness of 1.6 mm and a dielectric coefficient of 4.3. The

lowest layer of the proposed design was terminated with metal so that the S21

parameter was zero. The highest level of the absorber was formed from the

metasurface with a conductivity of 5.8.107 S/m. The design was simulated with the

CST microwave program. The results showed that more than 90% absorption was

achieved at the resonance frequencies of 3.06 GHz, 6.2 GHz, 18.48 GHz, 22.09 GHz

and 24.71 GHz. MATLAB program was used to obtain the results.