Research And Design Of Multi-beam Antenna Based On Metasurface

At present,with the rapid development of mobile communication and the increasingly complex communication environment,antennas need to have wide beam and multi-beam capabilities.A metasurface composed of periodic or aperiodic units on the subwavelength scale can control the antenna beam by adjusting the amplitude and phase of the incident electromagnetic wave.Based on generalized Snell’s law,this paper combines metasurface and microstrip feed antenna to carry out research on multi-beam antenna.The main work is as follows:1.Design of dual-beam antenna based on "E"-shaped structure metasurface.The electromagnetic properties of "E"-shaped metasurfaces are studied,and a single-beam planar microstrip antenna is used as the feed source,and a design method of low-profile dual-beam metasurface antennas is proposed.The analysis results show that at 8.7 GHz,the peak gain of the feed antenna is 7.7 dBi,and the gains of the dual-beam radiation are 8.65 dBi and 8.41 dBi,respectively.The designed antenna has the advantages of low profile and low price.2.Design of four-beam antenna based on rectangular structure metasurface.The working mechanism of the rectangular structure metasurface is studied and analyzed,and two rectangular structure units with 180° phase difference are designed.Combining the metasurface composed of this unit with a single-beam microstrip antenna,a design method of a four-beam metasurface antenna is proposed.The analysis results show that the antenna resonates at 8.82 GHz,and the gain of the four-beam radiation is about 7.32 dBi.3.Design of multi-beam switching antenna based on metasurface.The working mechanisms of three metasurface units are studied and analyzed,and PIN diodes are loaded on the metasurface.Controlling the voltage bias of the PIN diode can change the electromagnetic properties of the metasurface,and the metasurface can be combined with a microstrip antenna to achieve multi-beam switching.The analysis results show that at 9.28 GHz,when all PIN diodes are turned off,the antenna radiates four beams,and the beam gain is about 6.66 dBi;when all PIN diodes are turned on,the antenna radiates two beams,and the gains are 7.22 dBi and 8.2 dBi.