Research On Huygens Metasurface Electromagnetic Characteristics And Its Application In Antenna

Huygens metasurface(HMS)is a new type of metasurface.Compared with other metasurfaces,HMS can freely control electromagnetic waves because its structure consists of electric dipoles and magnetic dipoles,which can respectively control the electric response and magnetic response.Due to the outstanding ability in manipulating electromagnetic wave,the HMS is widely used in flat lenses,polarization converters,imaging systems and other devices.In this dissertation,the working mechanism of HMS is analyzed in detail,and two high-performance HMSs are designed.At the same time,the HMS is loaded on a horn antenna to improve the radiation performance of antenna.The main works include three parts as follows:(1)The design principle of HMS is introduced.Based on the Huygens equivalent principle,the generalized laws of reflection and refraction,and the Generalized Sheet Transition Conditions(GSTCs),we analyze the advantages of electromagnetic polarization used to represent the metasurface electromagnetic properties.Then we investigate the relationships among the Huygens metasurface transmission coefficient,reflection coefficient,electrical surface admittance and magnetic surface impedance.(2)We proposed a high-performance HMS with high transmission coefficient and full phase coverage.Based on the HMS,a beam deflection lens and a focusing metasurface lens are designed to realize the functions of plane wave deflection and plane wave focusing.Then,by loading the focusing metasurface lens to a horn antenna,the performance of antenna is greatly improved.Simulated and measured results show that the gain of lens antenna has been greatly improved in a wide frequency band range from 13.2GHz to16.6GHz(relative bandwidth 22.82%).(3)An anisotropic HMS is proposed to manipulate orthogonally polarized transmitted waves independently.Based on the HMS,a polarization beam splitter that can separate electromagnetic waves of different polarizations is designed.Furthermore,the designed polarizing beam splitter is loaded on a horn antenna to separate the radiation into two beams with different polarization state.