Terahertz Antenna Based On Graphene And Multi-Band Base Station Antenna Arrays

Terahertz has extensive prospects in industrial nondestructive testing,national defense security,biomedicine,communication and other fields,due to the low mobility of electrons and huge attenuation,the conventional metals are almost unfeasible for the design of efficient miniaturized antenna.Due to graphene has unique electronic properties in this part of the spectrum,this makes it an excellent choice of miniaturized antenna in millimeter/THz applications.Integrate future 5G antennas with existing 3G/4G antenna platforms will be one of the initial major challenges to building 5G wireless communication systems.This near-term complication will engender more stringent requirements on base station antennas,so it is now becoming imperative for the mobile industry to develop new antenna technologies to address the challenges in deploying5 G base stations antennas.Firstly,plenty of literatures on the design of antenna in domestic and overseas,achievement and research about graphene THz antenna,along with base station array antenna in recent years are retrieved,perused and summarized.Secondly,the basic knowledge and technical indexes of the antenna is described simply,and the theories of two kinds of antennas are introduced.Then,based on the conductivity formula and antenna design principle of graphene,three terahertz antennas are designed.The designs involve two reconfigurable nanoantennas,the operation frequency varies from about 0.74 to 1.26 THz and 0.92 to 1.15 THz,a tunable metasurfaces for two typical applications,the absorber can reach 0.835 ～ 1.02 THz bandwidth for reflectivity below-10 d B,and a reconfigurable terahertz Vivaldi antenna,the proposed antenna varies from about 210 to 670 GHz.Finally,the design methods of base station for 2G,3G and 4G communication are introduced systematically.The methods involve introducing chokes into low-band elements to suppress high-band scattering currents,and introducing chokes into feeding balun of high-band elements to suppress low-band scattering currents.As a demonstration,one of the choking techniques is implemented in a closely spaced dual-band array to suppress cross-band scattering.The simulated and measured results demonstrate that cross-band scattering in the array is largely eliminated,and the realized dual-band array has stable radiation performance in both high and low bands,The maximum gain of high-band and low-band of the arrays is 11.8 d Bi and 7.8 d Bi respectively.