宽带电磁超表面天线设计OA

To meet the requirements of next-generation wireless communication systems,a wideband electromagnetic metamaterial antenna is proposed.A metamaterial composed of hexagonal unit cells combined with inductive stubs serves as the radiator,which,compared to the conventional quadrilateral patch cell structure,offers higher coupling capacitance and longer current paths,thereby achieving wideband design objectives.To ensure high directivity in complex electromagnetic environments during practical applications,an additional metal ground plane is introduced at the bottom of the antenna,with Polymethacrylimide(PMI)foam filling the space between this metal ground and the main ground plane.A coplanar waveguide feeding structure is adopted,eliminating one dielectric substrate layer and resulting in a simpler,more fabrication-friendly design.The final antenna dimensions are merely 48 mm×48 mm×15.1 mm(0.473λL×0.473λL×0.149λL,where λL is the wavelength corresponding to the lowest operating frequency).Measurement results demonstrate that the antenna achieves an impedance bandwidth of 41.1%(2.96～4.49 GHz)for Voltage Standing Wave Ratio(VSWR)<2,with a gain ranging from 4.5 to 7.3 dBi across the operating band and favorable directional radiation characteristics.