| Metamaterials are artificial composite structures or composite materials with extraordinary physical properties that natural substances do not have.The emergence of metamaterials has greatly expanded the achievable medium space,and its unique electromagnetic characteristics have been widely studied and applied in many fields such as electromagnetic stealth,high-performance antennas,RCS and microwave devices.This paper uses a combination of theoretical analysis,numerical simulation and experimental testing to study the control characteristics of different configurations of metamaterials on electromagnetic waves,including wave absorption,polarization and transmission characteristics.The main research contents and results are as follows:(1)A metamaterial structure with different dihedral angles composed of planes is designed,and its electromagnetic characteristics are simulated and experimentally tested.The simulation results are basically consistent with the experimental results.Comparing the plane structure with the same parameters,under the incidence of TE and TM polarized waves,the main absorption frequency points are generated at 9.2GHz and 9.17GHz,and the corresponding absorption rates are 99.7%and 99.8%,respectively.Through RCS and 3D scattering diagrams,etc.The absorbing frequency points were verified.Compared with the plane absorbing effect,the composed dihedral metamaterial structure has the polarization-sensitive characteristics,can produce multi-frequency absorption peaks under the TM mode wave,and can effectively regulates the RCS.(2)A single-layer metamaterial is proposed.which not only has negligible thickness but also can be used as an optical beam splitter,which can achieve semi-transmission and semi-reflection of incident waves at the same frequency.It also controls the polarization conversion of circularly polarized electromagnetic waves in the transmission mode.The design uses the geometric phase theory to explain the principle of broadband operation,and the phase control can also be achieved through the azimuth rotation of the sample structure.The dihedral metamaterial reflector designed in this paper can be used for stealth technology,electromagnetic compatibility and target recognition.The designed single-layer metamaterial structure has the characteristics of simple structure and wide bandwidth,and can be applied to wireless communications,antennas,and sensing.It has important reference value for the integration of multi-functional ultra-thin devices. |
