Novel Reflective Phased Meta-Atom Array for Beam Forming along Multiple Planes

In this paper a novel beam-forming technique for focused microwave power transmission (MPT) at specific frequencies that enables far-field transmission at three directions in the elevation plane is proposed. A simple and planar phased metasurface comprising of an array of subwavelength meta-unit cells is designed to focus the microwave energy at 4.2 GHz at desired angles in the azimuthal and elevation planes. The beam formed is made to focus energy at <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0^{\circ}$</tex> by a suitably designed meta surface. The phase profile of the meta-atom array is then suitably tuned, to split the RF energy at elevation angles of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$70^{\circ}$</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$-70^{\circ}$</tex> directions in azimuthal planes of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$45^{\circ}, 135^{\circ},225^{\circ}$</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$315^{\circ}$</tex>. This ensures the compatibility of the designed reflective array surface with antenna radiators and hence, allows for the availability of power at different directions of focus. This functionality can be used to focus or deflect power in case of sensors placed at different locations in the far-field proximity of the main radiator. A patch antenna radiating at 4.2 GHz is used to conduct the simulation study using CST Microwave Studio.