【摘 要】
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Phase gradient metasurfaces (PGMS) offer a fascinating ability to control the amplitude and phase of the electromagnetic (EM) waves on a subwavelength scale,res
【机 构】
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Air and Missile Defense College, Air Force Engineering University, Xi’an 710051, China
论文部分内容阅读
Phase gradient metasurfaces (PGMS) offer a fascinating ability to control the amplitude and phase of the electromagnetic (EM) waves on a subwavelength scale,resulting in new applications of designing novel microwave devices with improved performances.In this paper,a reflective symmetrical element,consisting of orthogonally I-shaped structures,has been demonstrated with an approximately parallel phase response from 15 GHz to 22 GHz,which results in an interesting wideband property.For practical design,a planar antenna is implemented by a well-optimized focusing metasurface and excited by a self-designed Vivaldi antenna at the focus.Numerical and experimental results coincide well.The planar antenna has a series of merits such as a wide 3-dB gain bandwidth of 15-22 GHz,an average gain enhancement of 16 dB,a comparable aperture efficiency of better than 45％ at 18 GHz,and also a simple fabrication process.The proposed reflective metasurface opens up a new avenue to design wideband microwave devices.
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