Applications Of Metasurface In Leaky Wave Antenna And Reflective Array Antenna

Metamaterials have singular electromagnetic properties that are difficult to achieve with traditional natural media,and consist of sub-wavelength resonant units arranged in a specific manner.Simulation tool can be used to design the structure and size of the electromagnetic resonance unit can effectively control the equivalent electromagnetic parameters of the Metamaterials in a specific frequency band,thereby effectively regulating the characteristics and propagation state of electromagnetic waves.At present,Metamaterials have attracted the attention of researchers in many fields and have great engineering application value.Based on the metasurfaces,traditional leaky wave antennas and reflective array antennas are innovatively designed in this paper.The specific research contents are as follows:(1)The basic concept and working principle of a leaky wave antenna are introduced,and a single-beam waveguide leaky wave antenna working in the X-band is designed.By optimizing the width of the metal waveguide and the size and period of the ridges loaded therein,a higher beam scanning rate is achieved,and by optimizing the size and height variation of the periodic metal leaky pins that replace the narrow wall on the side of the waveguide,the leaky efficiency of the antenna is improved while reducing the side lobes.(2)A transmission-type cross-polar conversion phase gradient metasurface unit is designed.According to the generalized Snell's law,the metasurface phase gradient required to deflect the radiation beam of the single-beam leaky wave antenna to a specific angle is calculated.Based on this,the middle-fed and double-layer structure dual-beam waveguide leaky wave antennas are designed respectively,and the latter is processed and tested.The experimental results are in good agreement with the simulation results.(3)A transmission-type stealth material cladding is designed using a Jerusalem-shaped slot element structure for the Ku-band folded reflectarray with a focal length ratio of 0.23 and a maximum aperture efficiency of 34%.On the premise of ensuring the normal operation of the folded reflectarray,the reduction of the out-of-band backscattering radar cross section of the antenna system is realized,and the design of the low-scattering folded reflectarray system is completed.(4)The implementation method of the fixed polarized vortex electromagnetic wave antenna is introduced.Based on a group of anisotropic metasurface elements working in the Ku band with wideband characteristics,the design of the left-hand circularly polarized vortex electromagnetic wave antenna is completed.The correctness of the design idea is verified through simulation.