Research of Electromagnetic Waves Diffraction on Chiral Metamaterials of Different Frequency Bands

In the present work, the author synthesized and researched the properties of electrodynamically similar structures made of chiral metamaterial with resonant frequencies of 600 MHz and 900 MHz. From a practical point of view, a metamaterial structure, designed, in particular, for a frequency of 900 MHz, can be used to reduce the influence of cellular radio antennas on other antennas present at the radio-technical facility. Electrodynamics modeling and study of the diffraction phenomenon on electrodynamically similar structures made of chiral metamaterial based on helical elements when they are excited by plane waves of the corresponding range or half-wave dipoles have been made. The following effects were obtained: - the obtained resonant frequencies of metamaterial structures at different excitation methods are slightly different from each other; - the absolute values of peaks of induced currents during excitation by plane waves for different resonant frequencies are slightly different from each other; - frequency dependences of the peak current corresponding to excitation by dipoles are less oscillatory in nature. The observed effects are apparently associated, firstly, with the chaotic nature of distribution of chiral elements, and, secondly, with the different manifestations of diffraction effects at the edges of the structures during incidence of various electromagnetic waves.