Research Of Terahertz Communication Devices Based On Graphene

With the rapid development of the communication system, terahertz technology has attracted more and more attentions, and the terahertz communication has become hot spot in worldwide research. Compared to the microwave and millimeter wave band, terahertz has some unique performance, which has a far-reaching impact on the communication technology, national security, electromagnetic countermeasure, civil devices and so on. As the key to realize the application of terahertz, the development of terahertz devices is important. The requirements of size and performance of the terahertz device, make us need to find new materials to meet.As the focus of the current research in the field of materials,graphene has a lot of new characteristics better than other materials. The unique electromagnetic properties of graphene have important application value in terahertz communication. The terahertz devices made by graphene are small size, excellent performance and easy integration.Because the conductivity of graphene can be adjusted by the applied electric field bias, the graphene device can be tunable through a reasonable design. So the study of the communication devices in the terahertz frequency range is very important for the development of terahertz communication.This paper focuses on the graphene tunable conductivity and surface plasmon, researchs on the properties of graphene in the terahertz, designs the terahertz communication devices based on graphene, and analysis and calculates on its performance. The main contents of this paper are as follows:(1) Introduces terahertz communication and graphene, including the basic characteristics and applications of terahertz, graphene application and preparation methods, explains the meaning of the study of graphene device design,expounds the research status of graphene at home and abroad.(2)Introduces the basic properties of graphene electromagnetics,focuses on the analysis of the conductivity model of graphene and the characteristics of conductivity regulation.The characteristics of intraband and interband conductivity of graphene under different frequencies, and the Drude model of graphene and the dielectric constant are discussed,which lays the theoretical foundation for the design of graphene terahertz devices. In addition, the theory of surface plasmon excitation of graphene is discussed, and the principle of the surface acoustic wave is analyzed.(3)Study on the frequency control surface based on graphene. The circuit models of patch type and grid type FSS are studied, and their impedance and transmission characteristics are analyzed. Based on the analysis of the surface impedance of graphene under different chemical potential, the frequency selective surface and the high impedance surface are designed, and the simulation results are studied.(4)By analyzing the material properties of graphene and graphene Drude model, the propagation conditions, dispersion relations and propagation characteristics of the surface plasmon of graphene are studied.According to the properties of the conductivity of graphene and the surface acoustic wave properties of graphene, the design of terahertz radio frequency selective switch based on graphene is designed and simulated.