Optimization of parameters of absorbing metamaterials based on $\Pi$-shaped elements

On the basis of numerical simulation, the values of the parameters of an absorbing structure consisting of conductive $\Pi$-shaped elements which ensure the formation of weakly reflecting structures with simultaneous strong absorption of waves in the microwave range have been determined. Multicriteria optimization of the metamaterial parameters was performed using the MOGA genetic algorithm built into the DesignXplorer module of the ANSYS Workbench program. The period of the structure, the width and thickness of the conductive layer of $\Pi$-shaped elements were used as variable factors. The resonant frequency and the corresponding values of the reflection and absorption coefficients of the metamaterial were used as responses. The ANSYS HFSS program was used to design the absorbing structure and determine the response values. The numerical experiment was carried out using a sample obtained by the Latin hypercube method in the DesignXplorer module of the ANSYS Workbench program. The parameters of the metamaterial obtained as a result of optimization and the parameters obtained as a result of finite element modeling in the ANSYS HFSS program were compared. The maximum relative error of the results obtained using the MOGA algorithm did not exceed $1\%$ when determining the resonant frequencies of the incident radiation, $6\%$ when determining the absorption coefficients of the metamaterial, and $13\%$ when determining the reflection coefficients of the metamaterial.