Investigation of Frequency-Selective Surfaces Based on Graphite in the Absorption of Electromagnetic Waves

Abstract

Today, electromagnetic waves play an important role in our lives. These waves are used for radio and television communications, telecommunication networks and all wireless communications. Therefore, due to the widespread use of electromagnetic waves in the GHz range for mobile phones, national networks, radar systems, etc., it is a serious threat to human health. The presence of different electromagnetic fields and waves in space also causes improper operation or reduced efficiency in electrical and electronic circuits and components. Therefore, the issue of designing appropriate and efficient filters to protect electrical devices and maintain human health is doubly important. In this research, metamaterials and their application as absorbers in frequency-selective surfaces are studied. The design and development process of the frequency-selective surfaces based on graphite are presented in two steps. Finally, the performance of proposed structures with one and two hexagonal loops are discussed. The obtained results demonstrate that the base element consists of a hexagonal loop made of graphite filters the frequency band of 8–12 GHz. However, the base element consists of two hexagonal loops is able to filter the frequency band of 4–12 GHz. In fact, the proposed structure with two hexagonal lopps has filtered a larger frequency band.