Application Research Of Reconfigurable Antenna Based On Metasurface

With the development of wireless or satellite communication,the research of recon-figurable antennas function has become a frontier topic.Moreover,as electromagnetic metasurfaces are widely used in the research of antenna reconfiguration,this new type of metasurface antenna has better performance in reconfiguration.In this thesis,the electromagnetic metasurface is combined with the antenna,and a beam reconfigurable antenna based on the electromagnetic metasurface is designed ac-cording to the actual application requirements.The continuous reconfigurable function of the antenna beam in the cone area is realized by mechanical rotation.The main work of this thesis is as follows:1.A circular-polarized antenna array is designed and used as a feed antenna for beam reconfigurable antenna.The antenna design consists of two parts:element design and array design.The impedance bandwidth of the antenna is 16.6～23.3GHz.The antenna has an axial ratio range of 19.5～20.9GHz in the main beam direction.The second part is the design of the antenna array.Through the discussion of the array element spacing,the element spacing d=0.75λis finally determined,and a set of equal power division feeding network with 64 ports is designed for feeding.2.Two types of electromagnetic metashurface elements with high transmission and continuous phase modulation function are designed,which are stacked with multi-layer media.After synthesizing the characteristics of the elements such as polarization,inci-dence Angle and transmittance,the form of circular patch element nested circular patch is finally adopted,and the transmittance and phase modulation ability of the metashurface element under single layer media and multi-layer media are studied.Due to the lack of phase modulation ability of a single metasurface unit,a complementary design was car-ried out on the basis of the original,and the second metasurface unit was designed in the form of annular patch nested dielectric vias.Finally,the hybrid metasurface unit com-posed of the two metasurface units successfully met the requirements of the S₂₁<-1d B and has continuous 360°phase modulation capability.According to the needs,the hybrid metasurface elements are arrayed to form the phase gradient surface,and the beam deflec-tion performance of the phase gradient surface under the vertical and oblique incidence of electromagnetic waves is explored.3.A reconfigurable antenna based on metasurface is designed.In the first part,the plate array antenna is used as the feed antenna.According to the principle of lens phase compensation,the hybrid metasface element is used as the array element to compensate the phase gradient of the antenna aperture and realize the function of antenna beam deflection.Part II:A phase gradient metasurface array is designed and loaded in the near-field region of the beam deflecting antenna.The antenna pattern can be reconfigured by mechanical rotation operation,and it is processed and tested.