A Low-Profile Metasurface-Inspired Antenna With Tilted Beam Radiation

Abstract

In this letter, a simple method of generating tilted beam radiation through a planar structure is presented based on mode synthesis. Under the guidance of this operating principle, a low profile metasurface-inspired antenna emitting tilted beam is designed with the aid of characteristic mode analysis. The radiation structure of this antenna is a printed non-uniform metasurface. A broadside radiation mode is supported by an etched slot while a bidirectional radiation mode is excited by a metal via with a parasite microstrip line simultaneously. Consequently, a tilted beam radiation can be obtained by combining these two modes. To verify the analysis and simulation, the metasurface antenna is fabricated and tested. Measurement result indicates that this proposed metasurface antenna can realize a tilted beam at 5.1 GHz towards 35 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^\circ$</tex-math></inline-formula> with a realized gain of 7.9 dBi and a low profile of 0.048 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\lambda _{0}$</tex-math></inline-formula> ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\lambda _{0}$</tex-math></inline-formula> is the operating wavelength in free space).