Design of Transmissive Focusing Meta Array Using Wavefront Phase Compensation Technique for Wireless Power Transfer

In this work, a transmissive type focusing metaarray (TFMA) composed of sub-wavelength unit cells has been proposed to achieve efficient wireless power transfer (WPT). The wavefront manipulation has been achieved using the phase compensation technique resulting in a focusing meta-array. The phase tuned meta cells have been designed through full wave simulations with phase gradient coverage of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$2 \pi$</tex> maintaining transmission amplitude greater than <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$80\%$</tex>. The proposed system comprises an <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$11 \times 11$</tex> array of multi layered structure with accurately positioned meta cells. A horn antenna has been used as the feed host for impinging the array with electromagnetic energy to observe the near field focusing at distance of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{1 5 0 ~ m m}$</tex> away. Significant gain enhancement of 11.7 dB has been observed with the addition of TFMA at 8 GHz to achieve beam focusing at a single point for possible wireless power transfer application.