Research On High Performance Antenna Based On Metamaterial

Since the beginning of the 21st century,the development of mobile communication has been extremely rapid.From 2G and 3G to 4G in recent years,and 5G,which is about to be commercialized on a large scale,the communication speed is increasing,and the mobile handset is becoming more and more intelligent.In various communication application scenarios,an antenna is a device that receives and transmits signals,and its importance is self-evident.With the development of communication equipment to miniaturization,higher requirements have been placed on the performance of the antenna.People are eager to have high gain,miniaturization,low cost,wide frequency band and other characteristics,but in reality these antenna performance is not satisfactory.The emergence of metamaterials has opened up new ideas for the development of antennas.Because metamaterials have special electromagnetic properties such as high refractive index,negative magnetic permeability or negative dielectric constant,we can greatly improve the performance of the antenna by loading suitable supermaterials on the antenna.This paper mainly studies the application of metamaterials in improving antenna performance and provides new ideas for antenna design.The main contents of this paper are as follows:1.The metamaterials studied in this paper include vertical split ring resonators,vertical"gong"type resonators,and reconfigurable mushroom type electromagnetic band gaps.Based on the traditional split ring resonator and the planar I-type resonator,we developed it into a vertical structure to increase the gain of the vertically polarized antenna.Based on the traditional mushroom-type electromagnetic bandgap,we developed it into a reconfigurable super-surface to improve the performance of the antenna.2.We applied a vertical split ring resonator to the magnetic dipole antenna to create a high gain vertical polarization end-fire antenna.In the design of the antenna,we use the high refractive index of the metamaterial to increase its gain.After testing,its working frequency band is 6.4-6.7GHz,the gain reaches 8.7dBi,and the simulation is basically consistent with the test results.3.We designed a pattern reconfigurable Yagi antenna whose reflector is a metamaterial composed of a vertical"gong"type resonator,and the director is a reconfigurable mushroom type electromagnetic band gap.We placed a PIN diode array on the ground plane of the mushroom-type electromagnetic bandgap,and changed the electromagnetic characteristics of the mushroom-type electromagnetic bandgap by controlling the on/off of the PIN diode,thereby realizing the change of the antenna E-plane pattern.The antenna has two patterns:end-fire and tilt,which correspond to diode disconnection and conduction,respectively,where the main beam of the antenna is tilted by 24°in tilt mode.In these two states,the operating frequencies of the antennas are 8.9-9.4 GHz and 8.9-9.45 GHz,respectively,and the gains are 9.4 and 9.7 dBi,respectively.Simulations and tests have shown that the operating frequency band and gain remain essentially the same when the antenna pattern changes.On this basis,we have designed an antenna that has three operating states and the main beam can vary between±24°.Simulation and test results show that the operating frequency band and gain remain basically unchanged when the antenna pattern changes.